In EU decision-making, groups of member states are a well-established format. The new E6 group, comprising Germany, France, Italy, the Netherlands, Poland and Spain, nevertheless stands out. Unlike the Visegrád Four or the Nordic-Baltic Eight, it is not a regional grouping but instead spans the broad geographical spectrum of the EU, with the exception of Northern Europe. Nor is the E6 a classic coalition of interests, since its members hold differing positions, particularly on economic and fiscal policy issues. Rather, its composition is based primarily on size: Together, the six account for around 70 per cent of both the EU’s population and its economic output. Politically, the group is highly heterogeneous, with governments led by members of the Social Democrats (Spain), the liberals (France, Netherlands), the European People’s Party (Germany, Poland) and the national conservatives (Italy); among the finance ministers, the right-wing populist Patriots for Europe are also represented through Italy’s Lega. The E6 therefore resembles an expanded Franco-German motor that lays claim to representing a range of diverse positions, rather than a traditional EU grouping. 

The group can pursue its stated goal of injecting new momentum into stalled EU decision-making processes in two ways. The first is to seek a balance of interests combined with an implicit claim to representativeness. In the case of the Savings and Investment Union, for example, the E6 could feed jointly agreed positions into EU processes on issues where they have already negotiated compromises among themselves. This would replicate the advantages and disadvantages of the Franco-German motor on a larger scale: Acting together, they have the political weight to steer coordinated positions through the EU decision-making processes, but smaller member states with differing interests, such as Ireland, already fear being presented with a fait accompli.

The second approach would be to move forward as a vanguard group through enhanced cooperation, in which only willing member states would participate. Legally, the critical mass required for this is nine member states, so the E6 could not achieve this on their own. The aim, rather, should be to bring together as many willing EU states as possible, as in the case of financial assistance to Ukraine, in which 24 states are participating in enhanced cooperation. As some of the EU’s largest economies, they have the weight to form an attractive core for enhanced cooperation on economic instruments. However, the same applies here: If the E6 is to become not a governing body but a vanguard group, it will need openness and transparency vis-à-vis the other member states, as well as the involvement of the EU institutions. Only then can the E6 evolve into a genuine leadership format within the EU.

Resilience and capacity to act are currently the EU’s scarcest political resources. Geopolitical pressure demands swift decision-making, the ability to withstand shocks and the mobilisation of resources in times of crisis. This applies as much to joint military procurement, the protection of critical infrastructure and the defence against hybrid attacks as it does to securing supply chains and stabilising financial and energy markets. In this context, differentiated integration is gaining in importance: not as the familiar vision of concentric circles, but as a toolbox intended to open up new options where the EU’s official procedures would be too slow or too fragmented.

Academic analyses generally distinguish between three ideal types of differentiated integration. First, there are pioneer groups: They test solutions, pave the way for standards or provide initial seed funding. Their advantage lies in speed and learning effects; a potential weakness is that pilot projects may fail to generate a wider impact. Second, groups of like-minded states can break deadlocks where the EU-27 is stuck for political reasons or due to specific decision-making procedures. This approach carries the risk that those excluded may feel sidelined or form counter-alliances. Third, implementation coalitions that can also integrate states outside the Union are another option, for instance in procurement projects or in dynamic fields of action such as cyber defence. This can offer significant operational advantages; however, it may also entrench parallel systems that are difficult to reconcile within the EU’s legal and institutional framework.

In political practice, these ideal types can take different forms, whether through informal forums or through flexible mechanisms in the EU treaties such as enhanced cooperation; added to this is the phased integration of partner and candidate states. Minilateral formats such as the E6 also echo a G7 logic, in that major players shape the strategic agenda without an explicit mandate. How can this multi-layered differentiation of European integration be legitimised across different policy areas?

The fragmentation of the international order requires flexible responses that can withstand the demands of resilience. Differentiation is legitimate in the long term if it creates robust capacities for action while respecting European norms and remaining open to additional participants. This includes feedback loops, in other words a willingness to adjust chosen approaches to differentiated integration on an ongoing basis. It is also crucial that large member states view leadership not as a prerogative but as a service: Those taking the lead in Paris, Berlin, Warsaw or Rome must, above all, ensure that Europe is capable of acting externally while strengthening societal resilience within the Union.

The core of European integration is the European Single Market. The uniformity of this market of more than 450 million consumers with substantial purchasing power, governed by common rules, is the EU’s distinctive economic asset. There should therefore be no areas within this shared market that are characterised by permanently differing levels of integration.

The treaty conditions for using enhanced cooperation in Single Market regulation are stringent. The aim is always to strike a balance between economic policy regulation aimed at advancing one part of the Single Market and preserving the uniformity of the common market. This balance must be reassessed in each individual case. The European Court of Justice has granted the member states a relatively wide margin of discretion in making that assessment. 

Member states should nevertheless bear a number of basic parameters in mind: Particularly in the area of Single Market regulation, the instrument of enhanced cooperation should be used only as a measure of last resort, in other words as an absolute exception. There should already be a compromise supported by a majority of member states amounting to a qualified majority, which is being persistently blocked by only a very small number of member states. To prevent deeper fragmentation of the Single Market, no distinct areas, sectors or branches should be regulated using the instrument of differentiated integration. Only detailed provisions supplementing an existing regulatory framework in a given area should be completed by means of this instrument. 

The objective and guiding principle must be to maintain, safeguard and further consolidate the uniformity of the Single Market as the core of European integration at all times and across all market freedoms. In the priorities identified by the E6, the six largest economies, for closer coordination – the creation of a Capital Markets Union, strengthening the euro’s international role, joint defence investment, and cooperation on the procurement of critical raw materials and the security of supply chains – the issue is not, at least initially, European legislation but closer intergovernmental cooperation. Nevertheless, the EU’s “big players” must ensure that the gap does not widen too much between themselves and those who do not yet wish, or are not yet able, to move forward.

It is undisputed that political coordination within a group has repeatedly advanced the integration process, including in the regulation of the Single Market. However, where European legislation is concerned, the particular strength of Single Market regulation must be respected: The unity and uniformity of the Single Market are not only attractive to third countries, but also a powerful instrument of the Union’s economic and political resilience.

The E6 format is economically unique. It brings together the Union’s demographic and economic heavyweights and sits at the interface between opposing interests – from north to south, from east to west, and between eurozone insiders and outsiders. At the same time, it connects countries with traditional export- and industry-based models, such as Germany and Italy, with those that rely more heavily on modern technology hubs, such as France, Spain and the Netherlands. It also brings together the countries with the most problematic public finances (France, Italy) and the EU’s strongest advocates of fiscal discipline. Consequently, while the E6 format has great potential to forge compromises on key EU issues relating to capital market integration and banking union, it will also face the same challenges: the diversity of growth models, differing economic and fiscal positions, and particular national interests, all of which are further exacerbated by the domestic political constellations.

The EU already hosts multiple economic coordination formats, including the Eurogroup, so the E6 still needs to demonstrate its added value. Beyond promoting more strategic thinking within the EU, the E6 should focus on concrete projects, above all the integration of financial markets. With the exception of Poland, the E6 countries have the most developed capital markets. If they were able to agree on deeper integration in specific areas such as supervision, corporate bonds and market infrastructure within the E6 format, this would strengthen liquidity, cross-border investment and confidence in EU financial markets. The wide regulatory differences between the E6 countries, particularly in the financial and capital markets sector, lead to internal competition within the EU rather than giving these states a stronger collective edge in global competition. The greatest obstacle to such integration in the EU, however, remains the resistance to cross-border bank mergers – particularly in the EU’s largest economies – which hinders the emergence of genuine European financial champions. Without strong cross-border banking institutions, capital market integration will remain incomplete.

If the E6 format were to provide the impetus to overcome these obstacles, that would represent significant added value. Simply shifting existing EU disputes to a smaller format achieves little if the largest economies are not prepared to show greater leadership and a willingness to compromise. Given the competitive pressure exerted by the United States and China, capital market integration has now become a matter of urgency. What the EU needs is a vehicle for implementation, not another forum for discussion.

The group currently referred to as the E6 comprises countries that dominate agricultural production and trade. As a result, they also play a role in shaping how the EU can position itself in trade in general  – not least because the agricultural sector often becomes a risk factor in the conclusion of trade agreements. Current EU strategic responses to US tariff policy also frequently affect agricultural products. With the exception of Poland, all E6 countries rank among the world’s 10 largest agricultural exporters. In the case of wheat, France and Germany – and Poland as well – lead the way, whereas for butter, the frontrunners include countries outside the E6 group, such as Ireland and Denmark. The Netherlands, in particular, is the second most important exporter of agricultural products by value, just behind the United States. These six states also carry decisive weight for the future of the EU budget – 30 per cent of which is still allocated to agricultural expenditures – and for potential reforms to the common agricultural policy. To date, they collectively receive almost half of the agricultural budget; France, Spain and Germany in particular are by far the largest beneficiaries, whereas the Netherlands receives only a relatively small share.

Despite their collective relevance as a group, there are significant divergences of interest among its members, which in the past have repeatedly given rise to very different coalitions of individual member states depending on the agricultural or trade policy issue at stake:

In the debate on the future of agricultural policy, for example, Germany, France and Spain issued a joint position paper in 2019 that, among other things, emphasised a stronger environmental focus for agricultural payments. 

Trade agreements with a strong agricultural dimension frequently encounter resistance in France and Poland, as is currently the case with the EU-Mercosur agreement. Criticism of the EU-US agreement has also come from German civil society, driven by concerns of potential compromises on agricultural standards and consumer protection. 

Enlarging the EU often has triggered reservations among existing member states, for instance due to fears of losses in agricultural payments or competitive disadvantages. Faced with the agricultural giant and prospective new EU member state Ukraine, Eastern European EU member states responded to the EU’s trade facilitation measures for Ukrainian agricultural exports with their own national import bans, which are incompatible with EU competences.

Such an often highly dynamic, issue-driven coalition-building beyond the recently suggested E6 may intensify further in the run-up to the agricultural reform for the post-2028 period. The proposed new structures for agricultural payments may well fuel conflicts between member states by granting greater national leeway. This could jeopardise the geopolitically urgent need for a united EU position vis-à-vis trade agreements.

Since Russia’s full-scale invasion of Ukraine and Donald Trump’s return to the White House, questions of European security have been discussed primarily by heads of state and government in a range of bilateral and multilateral formats. It is therefore noteworthy that the E6 finance ministers are now seeking to strengthen the EU’s defence capabilities: By allocating budgetary resources, they determine the pace of rearmament and the equipment of the armed forces. Moreover, the E6’s composition makes it an interesting format. The EU’s most competitive defence companies are based in its member states. With Germany, France, Italy and the Netherlands on one side and Poland and Spain on the other, net contributors and net recipients within the EU are effectively brought into the same forum.

It would therefore be a significant step forward if the E6 were able to draw up compromise proposals. First, they have set themselves the goal of making defence a priority in the forthcoming Multiannual Financial Framework. For the time being, however, their positions still diverge widely on which policy areas should be cut in the EU budget to free up funds for financing defence expenditure through the EU budget. While France and Poland, for instance, are keen to maintain the EU’s high level of spending on agricultural policy, Germany remains opposed to alternative financing options, such as Eurobonds for defence. Reaching an agreement is essential, particularly because countries such as France and Italy, due to their high public debt ratios, will not be in a position in the coming years to raise the urgently needed funds to strengthen their own and Europe’s defence capabilities.

Second, the E6 would need a common line on which EU initiatives it intends to implement at national level. Here, the preferences of the European Commission and the member states conflict. The Commission’s security and defence policy proposals are aimed at greater competition, transparent tendering and procedural rules, and the creation of a Single Market for defence goods. This approach is at odds with the member states’ preference for intergovernmental agreements. In their aversion to supranationalisation in security and defence industrial policy, they leave unanswered whether their approach can generate innovation and growth across all EU member states and whether it is intended to lead to joint procurement. Against the backdrop of the current Franco-German dispute over the future of the two major bilateral projects – the main battle tank and the fighter aircraft – new approaches to intergovernmental cooperation in the field of core strategic capabilities are urgently needed. In this context, the principal task of the E6 finance ministers will be to address the framework conditions required for cooperation between EU states in defence policy.

In the current geostrategic environment, Poland is seeking ways to gain greater influence in Europe. Warsaw is therefore involved in or working with several minilateral formats, including the Weimar Triangle and its “Plus” variants, particularly in coordination with Germany, France, Italy and the United Kingdom (E5), as well as through close contacts with the Nordic-Baltic Eight (NB8). The focus of these groups lies primarily in the field of security and defence, and the EU is only part of their frame of reference. 

Participation in the E6 format also offers Poland the opportunity to engage in a cooperative arrangement addressing key financial and economic issues of European integration. First, Poland hopes to become part of a new decision-making centre with regard to financial and economic policy, for example on issues relating to the Capital Markets Union, and to better promote its ideas on competitiveness, European funding for infrastructure policy, industrial and energy policy, and defence procurement. Second, Poland sees the E6 as confirmation of its economic successes. As the only non-euro area country, Poland now finds itself within the EU’s group of economic heavyweights. Third, this is also significant because Poland has long harboured fears of marginalisation: Warsaw governments have viewed ideas about “differentiated integration” with caution, suspecting that the eurozone – of which Poland is not a member – could develop into an inner circle of European integration. As part of the E6, Poland now has the sense that it can help shape such developments. 

For Germany, Poland’s participation in the E6 initiative offers an opportunity to underpin the bilateral agenda with its neighbour in terms of European policy and to broaden its scope. It also signals inclusion in a potential pioneering initiative by actors beyond the eurozone. Particularly as the E6 gains substance, Germany should bear in mind that Poland occupies an intermediate position between the “northern” participants (Germany and the Netherlands), and the more “southern” states (France, Italy, Spain). On competitiveness and the prioritisation of defence spending, Warsaw is closer to Germany; on “common” financial instruments and the relaxation of budgetary rules, it is closer to the other participants. Germany should also intensify its dialogue with the smaller states of the eurozone and the EU on economic and financial issues. That could counter the impression that the E6 might evolve into a kind of new directorate.

The finance ministers of Germany and France have set out an ambitious agenda for the E6 format and brought the EU’s economically strongest states into the initiative. Given the geopolitical pressure facing the EU and its member states due to the wars in Ukraine and the Middle East, the US president’s tariff policy and the trade dispute with China, agreements within this format on competitiveness, defence and security of supply chains would be of crucial importance for the European integration process.

For Berlin and Paris, the E6 format offers opportunities. The Franco-German tandem has increasingly appeared overstretched and has tended to highlight its differences more than its areas of agreement. German European policy, for instance, aims first and foremost to create more favourable conditions for the German economy by improving the efficiency of the EU’s Single Market. For France, by contrast, the priority is strengthening European sovereignty vis-à-vis the United States and China. Paris views the EU and its regulatory framework as a shield against external economic and political influences. However, there is a threat in France that the far-right Rassemblement National could come to power in 2027, a development likely to have significant consequences for the bilateral relationship and for the EU policy of one of the founding member states. The E6 format would offer Berlin an opportunity to maintain dialogue with Paris in a supportive capacity.

Nevertheless, Paris and Berlin remain the key architects of Europe. They must use the E6 format accordingly to demonstrate their leadership role within a broader and more diverse circle. If they succeed, both will gain broader legitimacy for their priorities. The entire Union would then be more likely to endorse a compromise that combines competitiveness with the protection of the Single Market.

Should Berlin and Paris decide to maintain this format over the longer term, they must ensure transparency towards the other member states, particularly the smaller ones, regarding the topics under discussion, and refute the accusation that the E6 promotes a “two-speed Europe”. To build trust, the format could, for example, be designed with a degree of flexibility. Within the framework of an E6+, which should include additional states – in particular the country holding the Presidency of the Council of the European Union – the format proposed by Germany and France should not coordinate solely in response to external pressure. Alongside the European Commission, there is scope for a Strategic Blueprint-Designer to set the pace, making the EU fit for the future.