In her 2026 State of the Union address, European Commission President Ursula von der Leyen invited Canada to become an associate member of the EU. Beyond that, she remained largely silent on the question of enlargement.

There was no mention of Montenegro, which has closed half of its negotiating clusters—thematic groupings of the chapters that make up EU accession talks—and looks on track for membership by 2028. Nor did von der Leyen say what the union would look like if the solidarity she has voiced toward Ukraine were converted into membership.

The commission’s silence on these matters will be broken on September 30, when it presents its pre-enlargement policy review ahead of the October 15 meeting of EU leaders. The review was initially promised within the commission’s first one hundred days, with the three-hundred-thirty-day delay showing just how difficult these questions are to resolve.

That difficulty becomes particularly clear when it comes to decisionmaking in the EU Council. In the wake of former prime minister Viktor Orbán’s defeat in Hungary’s April 2026 parliamentary election, von der Leyen has called for wider use of qualified majority voting (QMV)—rather than unanimity—on foreign and security policy to stop national vetoes from hampering the EU’s ability to act in an increasingly volatile geopolitical landscape. But as Think Tank Europa’s new analysis of QMV in an enlarged union shows, extending this voting method to a potentially much larger union could carry far-reaching consequences that the commission will need to reckon with.

Enlargement could shift the balance of power in the council Eastward, diminishing the roles of countries like France, Germany, and Italy. On some issues, it is conceivable that a Polish-Ukrainian axis, which would represent 15.5 percent of the EU’s population, could become an anchor for future blocking minorities. As two major net beneficiaries of EU funds, both largely agrarian economies that rely on cohesion funding, Poland and Ukraine could raise concerns among more service-based and industrialized net contributors, particularly on the programming of the EU budget.

Working on the hypothesis that Ukraine’s accession would alter the power dynamics in the council under both the current voting rules and the proposed changes, the Think Tank Europa analysis shows that Ukraine, in combination with either Moldova or the Western Balkan candidates, would have been able to flip key contentious votes. The EU’s 2024 Nature Restoration Law, which narrowly passed, with states representing 30.9 percent of the EU population voting against, could have been blocked by Ukrainian opposition alone. As for the EU-Mercosur trade agreement, which passed only because Italy backed it at the last moment, an Eastern coalition of Hungary, Moldova, Poland, Ukraine, and the Western Balkans becomes a potentially powerful blocking force on trade policy.

In previous rounds of EU enlargement, issues related to voting procedures were resolved before new members were brought in. Leading up to the 2004 enlargement, discussions centered on Poland’s role as the largest of the incoming countries. When Poland joined, it was allotted twenty-seven votes in the council, roughly equivalent to Spain’s weight, despite the latter’s population being about 60 percent larger.

This arrangement reflected a three-way bargain: It preserved symbolic equality between France and Germany, which kept the same number of votes despite Germany’s population being roughly 39 percent larger than France’s; it secured Spanish ratification; and it made enlargement politically sellable in Warsaw. The deal also, however, gave Spain and Poland real blocking power, as it put them almost on a par with France, Germany, Italy, and the UK, which each held twenty-nine votes at the time.

As of this writing, no comparable reform is in place or even seriously on the table. The EU’s 2023 Granada Declaration promised that internal reform and enlargement would proceed hand in hand. Three years on, there is still no parallel reform track, and no sign that the pre-enlargement review will supply one.

Several proposals for reform do exist. Under QMV, votes need the approval of a majority of EU members that represent a majority of the union’s population. A Franco-German working group has proposed raising the threshold of members from 55 to 60 percent, while lowering the population threshold from 65 to 60 percent. The Think Tank Europa analysis shows that under this 60/60 model, blocking would become harder for the new members: Neither the Nature Restoration Law nor the EU-Mercosur agreement could have been blocked by an Eastern coalition including Ukraine.

But even under 60/60, important distributional questions remain. France, Germany, and Italy would stand to lose the most relative power, both under an enlargement scenario that keeps the current voting rules and under the proposed 60/60 arrangement. However, the ranking among them would shift: France’s power would be better preserved than Italy’s under 60/60, giving Paris a reason to support the proposal.

This reveals a second, independent effect: Switching from the current rules to a 60/60 formula would reduce large states’ power even without enlargement. Raising the state threshold would strengthen the principle that every state counts; lowering the population bar would make population size less decisive. Both changes would push toward a flatter distribution of power, regardless of whether the EU enlarges.

Whether or not this is a desirable outcome depends on where you stand in the union. However, these distributional questions will shape the compromises that the big three states of France, Germany, and Italy are willing to accept.

None of this needs EU treaty change to fix. Accession negotiations are conducted as an intergovernmental conference, and because the resulting accession treaty must be ratified by every national parliament, changes to voting rules could in principle be bundled into that same process. In practice, no such reform is on the table, and there is little sign of any appetite among EU members to use accession as that vehicle.

Inviting Canada to become the EU’s first associate member—a status that comes with no seat at the table and no vote to redistribute—is, by comparison, the easy part. Working out what the council looks like once Ukraine does have a seat is the harder question, and it is no wonder that it has taken the commission this long to prepare a satisfactory answer.