Is a Federal European Union Possible? Yes — But Not at Twenty-Seven
The latest vetoes by Hungary and Slovakia on the issuance of Eurobonds to finance the loan to Ukraine and on the twentieth package of sanctions against Russia, aimed at pressuring for the repair of an oil pipeline damaged by the bombings, once again raise the problem of unanimity among twenty-seven states in key areas such as foreign policy, defence, taxation, debt, the multiannual budget and financial revenues. The prospect of enlarging the EU to additional countries — from Iceland to Ukraine, including Montenegro and Albania — further aggravates this problem. Is it therefore possible to federalise decision-making in the Council to gain efficiency and legitimacy?
The short answer is not at twenty-seven, but yes through a vanguard group including the most populous states and those willing to advance European integration. Let us consider the different possibilities. First, the Treaty of Lisbon offers the possibility of activating the so-called passerelle clauses, through which many of these policies (with the exception of defence) could move to qualified majority voting — that is, 55 percent of the states representing at least 65 percent of the population. The problem is that this requires a unanimous decision by the Member States, which is highly unlikely, and in fact hardly any of these clauses have been activated since the Treaty entered into force in 2009. It is difficult to imagine Orbán, Fico or Meloni supporting a decision of this magnitude. Unfortunately, there will always be some Eurosceptic government willing to spoil the party.
The second possibility is the reform of the Lisbon Treaty itself, which is what the European Parliament proposed in November 2023 through a package of amendments eliminating most vetoes. This is an interesting avenue, since opening the reform process requires only a simple majority in the European Council. Of course, concluding it requires unanimity and twenty-seven national ratifications, including referendums in some countries. In such a scenario, the lack of support from all Member States would not necessarily lead to paralysis, since the majority in favour of the new Treaty could form a more integrated union while leaving the reluctant states aside. Unfortunately, so far, the European Council has refused even to take note of Parliament’s proposal, which suggests that there is no interest — at least for now — in assessing whether a majority of at least fourteen Member States could be assembled to trigger the reform procedure. The European Parliament can and must put more pressure in the European Council, by sending the project directly to national parliaments, convening an interparliamentary assembly, with citizens' involvement through deliberative panels, and eventually tabling an infringement procedure before the Court of Justice. These measures could receive the backing of the European Parliament if contained in an implementation report on the lack of follow-up on the Treaty reform procedure.
Finally, and without prejudice to the second avenue, the vanguard group could already be created through a coherent set of enhanced cooperations — a mechanism that already exists in the Treaty of Lisbon and allows a group of states to launch differentiated integration on a sectoral basis. The decision to establish an enhanced cooperation is generally taken by qualified majority, except in the case of foreign and security policy. Mario Draghi has expressed support for this approach, which he has described as “pragmatic federalism”. Integration will certainly not advance if it proceeds at the pace of whichever government happens to be the most Eurosceptic or nationalist at any given moment.
That said, it would not be reasonable to move towards a Europe of multiple different clubs: one for the euro, another for defence, another for a deeper internal market, and so on. This design could work if several enhanced cooperations were established with largely overlapping membership. To begin with, participation would require membership of the euro area (although this raises the issue of Poland), and then a willingness to pool foreign policy and defence, as well as certain fiscal and financial measures (harmonisation of indirect taxation, issuance of Eurobonds and new own resources), and to establish a dedicated budget for investment in the green transition and defence and counter-cyclical purposes — all under qualified majority voting. This would be possible according to the existing Treaties by activating passerelle clauses within enhanced cooperations where unanimity currently applies, combined with an intergovernmental arrangement renouncing the veto in the field of defence.
Moreover, within enhanced cooperations the ordinary legislative procedure applies whenever it is foreseen for the policy concerned, ensuring full participation of the European Parliament. If we imagine as a starting point the euro area without Slovakia and the neutral countries (Austria, Ireland and Malta — although the three might not necessarily remain outside), this federal core fully embedded within the EU would represent almost 75 percent of the Union’s population and 68 percent of its GDP.
In this way, this vanguard group would not need to create a new intergovernmental union outside the EU, although it might be useful to conclude an international treaty to accompany and complement certain aspects of this deeper union built through several symmetrical enhanced cooperations. If the governments of Germany, France and Spain were to launch such a proposal, the process of European unification would take a qualitative geopolitical leap vis-à-vis Russia, China and the United States. The seriousness of such a leap forward would have a strong traction effect, so many integration-reluctant Member States will prefer to join in rather than remain outside the federal core of Europe.
Brussels, 9 March 2026
Domènec Ruiz Devesa
President of the Union of European Federalists
Senior Research Fellow, CIDOB
Former Member of the European Parliament