Hosting European Union leaders in Copenhagen earlier this month, the Danish prime minister, Mette Frederiksen, described Europe as facing “the most difficult and dangerous situation since the second world war”. There have been other moments of high tension, such as during the 1980s when US cruise missiles were deployed in Germany in response to an escalating arms race with the Soviet Union. From next year, long-range missiles will be back on German soil, amid fears that recent Russian incursions into EU airspace herald a new and ominous phase of the war in Ukraine.

As Donald Trump’s US continues to carry the status of an unreliable ally, European unity, cohesion and solidarity are of critical importance. But little of substance emerged from the Copenhagen talks. Disagreement persists, for example, over the advisability of leveraging €140bn of frozen Russian assets to assist Kyiv.

As leaders contemplate a potentially lengthy and complex hybrid conflict with Russia, a European Council summit next week will need to make some concrete decisions. On one matter, however, there is already a consensus. Soon after Vladimir Putin’s illegal invasion in 2022, Ukraine was granted candidate status to the EU, along with neighbouring Moldova. Yet Viktor Orbán’s Hungary continues to block the progress of accession talks, a position that he reiterated in Denmark.

Opposition to the liberal values for which the union stands has long been a badge of pride in Budapest, as Mr Orbán has positioned himself as the EU’s enemy within on issues such as minority rights and civic freedoms. Since Russia’s invasion of Ukraine, that approach has been extended to EU foreign policy in ways that demand a more effective response than hitherto. Hungary has repeatedly delayed the introduction of EU sanctions on Moscow, made unilateral overtures to Mr Putin, and steadfastly maintained its reliance on Russian oil and gas. In continuing to block Ukraine’s and Moldova’s route to EU membership, Mr Orbán is compromising a dimension of Europe’s future security strategy in the face of Russia’s aggression.

Given that moving through the various phases of the accession process requires unanimous approval, the question is what can be done about it. The president of the European Council, António Costa, recently proposed changing voting rules to allow a qualified majority of member states to progress talks. But to do that would itself require Mr Orbán’s assent. More promisingly, Brussels now appears ready to bypass the technical requirement of seeking formal approval from national capitals at each stage, allowing Ukraine and Moldova to proceed with necessary consultations and reforms.

Such a solution would have a morale-boosting effect in Kyiv, at a time when Mr Orbán is making opposition to Ukraine’s accession a wedge issue ahead of Hungarian elections next spring. Moldovans also deserve to reap the benefits of the country’s remarkable national poll last month, when the ruling pro-EU party won an absolute majority of the vote despite widespread Russian interference.

Last week, Mr Orbán accused Ukraine’s president, Volodymyr Zelenskyy, of using “moral blackmail” to pressure member states over accession. In reality, it is Hungary’s prime minister who is making unscrupulous use of his power to disrupt EU foreign policy. Narrowly trailing in the polls, Mr Orbán may be gone after next April’s election. For now, he needs to be worked around.

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