Europe’s Next Enlargement

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EU enlargement has entered a critical phase. Amid geopolitical urgency and a US-led push to end Russia’s war on Ukraine, the European Commission developed several options for accession reform. The proposal that centered on fast-tracking Ukraine’s membership by formally bringing the country into the EU first and then conditioning full access to meeting criteria later has faced pushback from member states. On March 4, EU ambassadors reportedly refused this option, which is known as “reverse enlargement” or “phased integration,” and asked the Commission to find a realistic way forward. 

If the Commission is tasked to continue under the current accession model, more focus should be given to the two so-called Balkan frontrunners, Montenegro and Albania. Having recently achieved impressive results in their respective membership talks, they now stand a realistic chance of finishing them in the period from 2027 to 2028. While their membership prospects have been recently overshadowed by the centrality of Ukraine in the EU’s enlargement debate, they now certainly deserve more attention. Montenegro, for example, has already closed almost half of its negotiating chapters. Consequently, in December 2025, EU member states proposed to start drafting the accession treaty for its entry into the EU. As the last accession treaty was concluded with Croatia 15 years ago, this presents a further challenge for officials in Brussels and national capitals. They will have to include stronger safeguards against new members backsliding on commitments made during negotiations on EU membership, particularly on the rule of law. Adding to the pressure, the accession treaty with Montenegro, according to European Commissioner for Enlargement Marta Kos, will serve as a blueprint for the next generation of EU accession treaties. 

There are internal hurdles to clear within the EU before the first candidate can realistically receive the green light to join the bloc. However, in an increasingly volatile world with transactional great-power competition – and with two wars on Europe’s threshold – the window of opportunity for enlargement is there. In fact, EU leaders should be discussing this prospect as a matter of urgency. After all, enlarging the Union can be a key instrument to promote security and stability in its neighborhood and stay relevant in global geopolitics. 

Despite reservations about “phased integration,” revising the accession model is not completely off the table. Still, whether EU leaders will succeed in taking joint decisions on widening and reforming the Union is not yet clear. That will depend on a Ukraine peace deal putting pressure on the EU and Montenegro ­arriving at the finish line of its technical process – or the August 2026 referendum in Iceland succeeding and creating the prospect for the swift accession of this Nordic state that is already part of the European Economic Area.

Next decisions on enlargement, as well as the timeframe for accession reform, are now firmly in the hands of EU member states. As ever, their leaders must balance competing priorities and objectives while their own governments, parliaments, and societies might not be fully onboard with expanding the EU.

Given the dominant position of the member states in the accession process, this paper takes stock of the situation in Germany, France, and the Netherlands, whose governments play a critical role in this policy dossier. It finds that, while diplomats in Berlin, Paris, and The Hague are becoming better prepared to rethink parameters for the next enlargement, political leaders there have yet to take sufficient interest in this issue. While public discourse and national debates remain limited, there are also signs of increased interest. Against this background, we put forward recommendations on how to navigate some of the key obstacles.

GERMANY: Small Steps Toward Some Momentum

The German debate on EU enlargement is beginning to gain some momentum, at least within government corridors. Previously, Berlin had been passive on this issue, taking a typical “wait and see” approach. In recent weeks, however, it has geared up into a more proactive phase. Initially, strategizing among Germany’s main institutional actors – the Federal Foreign Office, Federal Chancellery, and German Bundestag – was very fragmented and focused on supporting Ukraine. But it has gradually led to better clarification of national positions and the formulation of ideas on how to revive accession that was largely driven by the anticipation of the Commission’s proposals on accession reform.

Behind closed doors, high-level officials and politicians acknowledge that enlargement needs to be seen through “geopolitical logic.” At the same time, they also emphasize the need for applying the Copenhagen criteria and a merit-based approach to candidate countries, particularly in area of the rule of law. The major question from the German side is how to fast-track Ukraine while “stitching” it to the merit-based approach. For the moment, the mood in Berlin is more open to innovative elements in the accession framework that could infuse it with more dynamics that provide more substance for gradually integrating candidate countries while keeping full membership solely as a final goal. 

Chancellor Friedrich Merz has not yet taken sufficient interest in EU enlargement. So far, his attention to these issues has been very limited and sporadic, mostly driven by diplomatic occasions and external impulses. At the 2026 Munich Security Conference, he answered a question from Montenegro’s President Jakov Milatovic with personal conviction, saying that he felt “more and more uncomfortable” with the current approach to enlargement. The chancellor added that the EU needs to revive its strategy with regard to bringing the Western Balkan countries “closer and closer” to the EU “and, at the very end, [have them] as members.”

Within Germany’s current ruling coalition, the enlargement dossier sits firmly in the hands of the center-right Christian Democratic Union (CDU). For the first time in six decades, both the chancellor and foreign minister are from the CDU. This constellation gives the junior coalition partner, the center-left Social Democratic Party (SPD), little say on EU enlargement. The internal deliberations of the CDU will be shaped much more extensively by its own sister party, the Christian Social Union (CSU), which takes a more skeptical approach to enlargement. The CSU has expressed a clear preference for prioritizing internal reforms and impact assessment in the next EU budget before any decisions are made on a new accession model. Notably, Germany’s domestic politics will be influenced by a series of important regional elections as voters in five out of Germany’s 16 federal states cast their ballots in 2026. The results of these elections are widely seen as a key test of the national mood as the far-right Alternative for Germany (AfD) competes for first place in national polls with Chancellor Merz’s conservatives.

Strategic Approach and Bilateral Interests 

On Ukraine, Germany is the largest European donor and provider of military, financial, and humanitarian assistance. Its primary objective has always been to ensure the survival of Ukraine as a sovereign, independent state. Berlin has also been a consistent – and crucial – supporter of Kyiv’s EU-related reforms in the areas of the rule of law, fight against corruption, and decentralization. But Germany’s focus has been on Ukraine’s short-term needs in terms of defense, economy, and diplomacy vis-à-vis the shifting role of the United States rather than on its EU future. That might be part of the reason why the Commission’s push for accession reform has initially raised more concerns in Berlin than enthusiasm. After President Volodymyr Zelensky repeated 2027 as target date for EU accession a few weeks ago, Chancellor Friedrich Merz rejected such a prospect outright. Foreign Minister Johann Wadephul is said to be against a sui generis approach to Ukraine, preferring a package deal with the two Balkan frontrunners (and potentially Iceland) instead. 

Moreover, the Foreign Office considers the internal EU reform agenda crucial. At this stage, however, the Commission’s focus is almost exclusively on enlargement. The German government criticizes that Brussels has not sufficiently reflected on the internal reform dimension and pre-accession policy reviews. 

Berlin sees Montenegro as a solid frontrunner and a potentially low-cost success story that can become a catalyst for further enlargement momentum in the Western Balkans. To increase Montenegro’s political profile in Europe, German diplomats convinced the government in Podgorica to chair the so-called Berlin Process format of regional cooperation for this year. Meanwhile, Albania will continue to be seen as below a critical threshold until it gets a positive Interim Benchmark Assessment Report (IBAR) from the Commission. Berlin tends to make a stricter assessment of the recent high-profile corruption cases in Tirana than other member states. It wants to see suspected ministers not only dismissed from government but also properly investigated by special prosecutors. 

The Merz government tried to keep the door open for Serbia. German conservatives see the prospects for a successful EU integration of the entire Western Balkan region as closely linked to the accession of its largest country. Another factor is party politics: the ruling party of Serbia’s President Aleksandar Vucic is associated with the same European political family as Germany’s CDU/CSU although it is currently facing an internal scrutiny process over democratic backsliding at home. In any case, Belgrade’s failure to deliver on its previous EU commitments on the rule of law, combined with its harsh treatment of student protesters and persistent ties with Russia, made any upgrade of Serbia’s accession talks in 2025 politically untenable for Berlin – and a controversial topic among the partners in Germany’s ruling coalition.

Another membership candidate proactively mentioned in Berlin nowadays is Iceland. As the country is already integrated into the EU single market and the Schengen Area, Iceland could reinforce the German instinct to focus on low-hanging fruit – small countries, easy ­cases – before turning to more complex and challenging cases like Ukraine, Moldova, and North Macedonia.

The latest Eurobarometer shows that 49 percent of respondents in Germany view enlargement positively, which is slightly below the EU average. Perhaps also reflecting this relatively weak public support, the German Bundestag has been a comparatively weak actor on EU enlargement so far. Although bilateral and security issues in the Western Balkans have often been on its agenda, discussions have more often focused on routine prolongations of the EUFOR and KFOR peace missions rather than on the region’s integration into the EU or its membership prospects. However, both the Bundestag and Bundesrat (the two bodies that make up the legislative branch of Germany’s federal government) will play a central role in the ratification of any new accession treaty. In both chambers, the grand coalition of CDU/CSU and SPD that currently rules Germany will need to turn to the opposition to ratify any accession treaty with two-third majorities. Consequently, a regional state government potentially led by the far-right AfD would not be able to block ratification, but it could increase the political costs for the centrist parties. 

THE NETHERLANDS:
Not (Yet) Ready for Fast-Tracked Enlargement

The new Dutch center-right government installed in February 2026 is clear about its European ambitions. Consisting of three parties – the progressive liberal Democrats 66 (D66/Renew), the conservative liberal People’s Party for Freedom and Democracy (VVD/Renew), and the Christian Democratic Appeal (CDA/EPP) – its coalition agreement states that “the Netherlands must be the driving force behind a geopolitical and strong European Union that acts decisively.” This includes ambitions for moving forward on EU enlargement that are discussed in the very first bullet point of the agreement’s chapter on Europe.

However, with only 66 out of 150 seats in the House of Representatives, the minority government will be ­dependent on other parties to realize its goals. Continuous negotiations between the coalition and opposition may lead to concessions in virtually any policy field. In the Dutch Parliament, EU enlargement is traditionally prone to ending up as a bargaining chip. Moreover, political and administrative elites fear that quick enlargements risk destabilizing the EU as it functions today. Since Dutch citizens still seem to be in the dark about the benefits of enlargement, much will depend on the willingness and ability of the new government to address public opinion and understanding for this issue. 

Dutch Discussions on Fast-Tracked Enlargement

The new government coalition wishes to approach enlargement “realistically” and “geopolitically,” but candidates “must continue to comply with the Copenhagen criteria to become a full member.” This includes Ukraine, on which the coalition agreement explicitly mentions adherence to rule of law conditionality. While the agreement also welcomes the concept of a multi-speed Europe, its exact meaning remains unclear. This may refer primarily to ideas about advancing EU cooperation in core groups of member states. Whether and how an EU model of different speeds would apply to current candidate countries is not elaborated. 

Arguably, political thinking about fast-track procedures or major accession reforms is in the early stages in the Netherlands. Only one year ago, as the party leader of D66, current prime minister Rob Jetten – together with Laurens Dassen, the party leader of Volt – filed a motion prompting the government to commit itself to a fast-tracked accession of Ukraine. While the GroenLinks-PvdA, which is currently the main opposition party in the Netherlands, supported the motion, it was opposed by the rest of parliament, including CDA and VVD, and therefore rejected. The vote thus revealed key political differences among the three coalition partners on the issue.

Recent parliamentary debates on enlargement have not discussed any major enlargement overhauls. A debate (written procedure) held in December 2025 just prior to the EU’s General Affairs Council serves as an example. At that time, Dutch Parliament did discuss accelerated EU integration for Ukraine and other candidates but only as an instrument to achieve greater integration before actual accession. As such, it merely reflected the current accession methodology. 

Discussions in Dutch Parliament have also remained focused on traditional pre-accession conditionality for the Balkan candidates, including the so-called frontrunners Montenegro and Albania. Hence, fast-track accession does not appear to be on the agenda for these candidates either. So far, a parliamentary majority has recognized reform achievements in Albania and Montenegro, agreeing with EU steps to open clusters (Albania) or close chapters (Montenegro). But real Dutch commitment to the EU’s self-proclaimed enlargement momentum will only become clear once these countries finish their negotiation procedures and require decisions about their actual accession.

A 2025 Eurobarometer did find that public opinion in the Netherlands is relatively supportive of EU enlargement. With 69 percent of the Dutch (somewhat) in favor, the Netherlands ranks 9th of 27 member states. Still, Dutch politicians are usually wary of Dutch public opinion on the topic. Although the Dutch generally support Ukraine out of geopolitical solidarity, similar sentiment is largely absent toward other candidate countries. Because public discussions on enlargement hardly take place, the topic is not salient among the Dutch population. This means that, in the run-up to potential big decisions on enlarging the Union, the government needs to step up its public engagement or risk the population feeling uninformed – as was the case in previous enlargement rounds.

Next Steps from the New Government

In December 2025, former Prime Minister Dick Schoof commented on the US and Ukrainian proposal to include EU membership as part of the security guarantees for Ukraine. He noted that Ukrainian EU membership cannot be part of any peace negotiations but must be decided upon by the EU itself. In practice, though, a wider Ukraine peace agreement may well put immense political pressure on the EU to accelerate the process with that country. Therefore, behind the scenes – unlike in public political discussions – Dutch diplomats and advisory bodies like the Advisory Council for International Affairs (AIV) are analyzing and preparing for various scenarios, including a fast-tracked Ukrainian accession. Should things go that way, the Netherlands can be expected to insist on rigorous and strict post-accession conditionality with suspension of most membership rights such as voting rights in the Council or participation in all EU policies. Critics refer to this as B-status EU membership.

While diplomatically prepared, the Netherlands is likely to remain politically reactive, awaiting further proposals from the European Commission. The Hague may also await greater clarity on the positions of member states like Germany and France, which so far do not appear inclined toward major overhauls. Most political parties in the Netherlands hardly discussed enlargement in their party manifestos for the 2025 general elections, let alone offer proposals for revising the process. Therefore, any major overhaul of the EU’s enlargement methodology to account for the fast-track accession of any candidate will certainly meet fierce discussion in Dutch Parliament, where parties opposing or holding major reservations about enlargement hold more than one third of the seats.

At the same time, there are precedents of Dutch Parliament reconsidering previously rigid positions. ­After years of principally rejecting an EU membership perspective for Eastern European countries, the parliament embraced doing so for Ukraine and Moldova in 2022 following major political pressure from other member states. If confronted with new geopolitical realities such as those created in a potential Ukraine peace agreement, another turnaround may occur. ­Given the outcomes of various polls on the topic, selling fast-tracked enlargement to the Dutch population could be possible, but it would require politicians to embrace a more open and sincere public discourse about the incentives and expected impact of such a step. It remains to be seen if the new minority government is up for that challenge.

FRANCE: Slowly Making Haste

At the moment, French authorities do not want to spark a public debate on enlargement in France. According to a Eurobarometer poll, the French are the least supportive of further enlargement among the EU-27 with 43 percent of respondents in favor and 48 percent against. Another recent survey found that public support for Ukraine in France is backsliding compared to levels in 2022. Consequently, the government of Prime Minister Sébastien Lecornu is careful not to draw political attention to an issue as controversial as the accession of Ukraine or any other candidate country, especially in the domestic context of its lack of a parliamentary majority and in the run-up to presidential elections in 2027, which has already begun. This spring, the government in Paris is investing its political capital on EU affairs mainly in promoting European preference schemes in public procurement to safeguard European industries – the so-called Industrial Accelerator Act – and rearmament. 

Moreover, despite President Emmanuel Macron’s shift away from France’s historical reluctance on EU enlargement that he laid out in his speech at GLOBSEC Forum 2023 in Bratislava, France’s public administration remains wary. High-level diplomats show a puzzling French ambivalence toward enlargement, speaking positively on it publicly (“Ukraine must join as soon as possible”) while questioning each move in the negotiations from behind closed doors. In December 2025, the Danish presidency of the Council had to deal with France’s initial refusal to close two new chapters with Montenegro before it finally agreed. Paris also resisted setting up a working group on drafting the accession treaty for Montenegro. The Quai d’Orsay, as the French Ministry for Europe and Foreign Affairs is known, generally finds the Commission’s assessments of candidate countries to be too proactive on enlargement. 

Strategic Approach and Bilateral Interests 

Opposing views on European integration exist within the French administration. Traditionally, the Quai ­d’Orsay sticks to a conservative approach while the powerful Ministry of the Economy, Finance and Industry, and Digital Sovereignty of France is more open to out-of-the-box thinking. France opposes the idea of “reversed enlargement.” Benjamin Haddad, the French Minister Delegate for Europe, recently declared that “enlargement must remain demanding and merit-based to ensure its success and credibility.” Yet he added that candidate countries should not be left “in a gray zone, vulnerable to foreign influence and aggression.”

In the case of Ukraine, there is some understanding in the French government that the usual merit-based approach must be bridged with the geopolitical imperative raised by Russia’s invasion and its threat to Europe. The Elysée, the office of the French president that keeps a close eye on all EU affairs as part of its domaine réservé (the traditional albeit non-constitutional authority of the French president to take the lead on foreign policy and defense), has circulated a non-paper to test ideas on ways to address this challenge for enlargement. 

Beyond Ukraine, France now welcomes the perspective of EU membership for Montenegro and Albania by the end of this decade. President Macron also considers it critical for the EU to keep Serbia on board and maintains close personal ties with President Vucic. The French Ministry for Europe and Foreign Affairs views this Western Balkan country as strategically key to the next wave of accessions. Historically, Serbia is France’s main ally in the region and has committed to major investments involving French companies, not least in defense. Paris considers it geopolitically more risky to keep Belgrade out than to tie it to the EU. France pushed for opening cluster 3 on competitiveness and inclusive growth with Serbia in late 2025, but it did not have sufficient support among the EU-27 to get it through. Paris also favors decoupling Moldova from Ukraine and starting separate negotiations with Chisinau should Hungary continue to veto Kyiv after its parliamentary elections in April. 

Further, France does not want enlargement to go ahead without prior – or at least parallel – internal EU ­reform. It acknowledges that an accession of just the two front runners would not necessarily require a review of the EU’s current organization, arguing that the EU already had 28 members before Brexit. But, regardless of enlargement, Paris considers the EU’s decision-making process unfit for crisis management. Advisors and circles close to the Elysée find it necessary to focus on moving to qualified majority voting by reviewing the provisions in article 7 of the Treaty on European Union to make it work. They also aim to enhance the role of the European Council, which is historically a French creation and dear to the Elysée. Traditionally, it has been very much in favor of differentiated integration, meaning addressing specific issues (i.e., the savings and investment union) by reinforcing cooperations or building separate coalitions of the willing within the EU-27 or even mixing with non-EU members.

The constitutional requirement to ratify any new accession treaty by a three-fifth majority in both chambers of the French Parliament (Assemblée Nationale and Senate) or through a referendum remains France’s biggest political impediment to fulfilling the promise of enlargement. Seriously addressing this obstacle seems impossible before next year’s presidential election, which has so far resulted in embarrassment rather than operational proposals to overcome it. The current government constellation would favor attempting parliamentary ratification over taking the political risk of a referendum bound to fail. But, given the surge of the Far Right, neither path would be an easy ride politically. The European Commission is well aware that France can end up as the major hurdle on the road to enlargement, which is why Enlargement Commissioner Marta Kos intends to engage more with the country. The Commission and the Quai d’Orsay are planning some targeted communication initiatives in this regard. Public communication efforts around enlargement will have to especially reassure farmers who are worried about Ukraine’s impact on the EU’s Common Agriculture Policy (CAP).

Policy Implications and Recommendations

Given the perspectives on enlargement in Germany, France, and the Netherlands described above, we ­offer the following recommendations. To move the enlargement process forward, member states should:

• Take the lead now – and maintain the momentum: The Commission’s proposals on accession reform triggered more interest among German, Dutch, and French diplomats and government officials on how to operationalize enlargement. After the Commission did its part, member states should now take the lead in the policy debate on the flexibilization of the accession procedure. After the principle of “reversed accession” was dismissed, the option of “enhanced gradual integration” deserves more work and attention in national capitals. Because the current window of opportunity might not last long, the Council should not waste the current momentum and aspire to come up with clear instructions for accession reform before mid-2026. Later this year, the domestic political outlook in France and Germany is set to become more difficult and less conducive for bold decisions on EU enlargement.
   
• Clarify policy impact: In a difficult geopolitical environment, the first candidates are moving toward the finish line of accession. This challenges the governments of EU member states to clarify which common policies and resources will be open to future members and which will be kept closed to them. Serious attention should be paid to the modalities of extending the Common Agricultural Policy (CAP) and cohesion policy. Yet, at the same time, it would be unwise to restrict the four freedoms – especially the free movement of people – from countries entering the EU beyond the standard optional transition periods.
   
• Reassure frontrunners: Montenegro and Albania should be tackled under the current accession methodology and be given more assistance to finish their membership talks. A potential second-class membership with many safeguards will disincentivize further reform. Such “political membership” would reward current political elites, giving them a seat at the EU table (though possibly no veto), but not necessarily the citizens of the Western Balkan candidate countries who would have relatively little to gain from it. That is clearly not the case in Ukraine, however. There, any formal accession to the Union carries political weight and could play a part in conflict management – if not conflict settlement.
   
• Prioritize communication and public outreach: Enlargement has now entered a critical phase. With Iceland preparing for a referendum in August on renewing its own EU membership talks, there is too little attention paid to this policy area across the EU-27. Politicians in member states should drive national debates on enlargement in a balanced manner, earnestly discussing its potential benefits, risks, and safeguards. In addition, leaders and governments throughout the EU should stress the geopolitical significance of enlargement at a time when Europe’s security is threatened. 
   
• Articulate the advantages of integrating the Western Balkans (as well as Ukraine and Moldova): Many national debates are likely to focus on the risks of EU enlargement, but they should also explain the contributions future members could make to common EU policies and objectives. For the Western Balkan candidates, that includes highlighting three areas: 
  1. Bolstering security and defense: Albania and Montenegro are already NATO members and therefore involved in strengthening the eastern flank, but more can be done to foster wider defense industrial cooperation;
  2. Combating illegal migration from third countries: This challenge to enlargement from the Far Right needs to be defused; and 
  3. Contributing to the green economy and industries of the future: Even modest additions from candidate countries could help improve EU competitiveness. The Commission could join forces with business associations in member states with low perceptions of enlargement, such as Germany, to engage them in public outreach with this in mind. 
      
• Form coalitions of the willing: Germany, France, and the Netherlands should actively look for like-minded EU partners, proceeding from internal debates and national papers on enlargement to joint non-papers at the EU level. On the one hand, this could bring forward some fresh, pragmatic views on how the Commission could retool the accession framework. On the other hand, it might take small groups and coalitions of the willing to overcome the current stagnant, often narrow outlook on enlargement and put it onto more strategic footing. This was how more forward-looking perspectives were recently achieved on competitiveness and some other EU policy dossiers. 
   

The coauthors would like to acknowledge lliriana Gjoni of Carnegie Europe for her very helpful feedback and support during the drafting process. They would also like to thank DGAP’s Stefan Meister and Linn Selle for their valuable comments on earlier versions of this paper.