Hungarian Prime Minister Viktor Orbán has popped the bubble of enthusiasm in Brussels for allowing Ukraine in as a new European Union member state, warning that “very difficult” questions need to be answered before the bloc can absorb an active war zone into its territory.

European leaders have been pushing to considerably accelerate the process of making Ukraine an EU member state, which typically takes many years and involves candidates meeting what are known as the Copenhagen accession criteria. The list of minimum entry requirements includes “stability of institutions”, “a functioning market economy”, the ability to uphold EU law, and protections for democracy, human rights, and minorities.

Many of these may be difficult to achieve during a major war, where to supposedly further the undeniably important goal of defeating the Russian invasion and occupation elections have been suspended, opposition political parties outlawed, military-age males banned from foreign travel, and corruption issues persist.

Cutting through talk of Ukraine joining the European Union despite these issues as a simple matter of obeying the “call of history” and ignoring the Union’s own rules, Hungarian leader Viktor Orbán said “very difficult questions” had to be asked.

Speaking to Hungarian radio this week, Reuters reports, the prime minister said: “We cannot avoid the question – when during the autumn we will have negotiations in Brussels about the future of Ukraine – whether we can actually seriously consider membership for a country, to start accession talks with a country that is at war.”

Orbán questioned how wise it was to admit a new member that does not have a clearly defined territory — swathes of the country including Crimea have been under Russian occupation for nearly a decade now — and which has an unknown population as refugees continue to flee, but also return home.

“To admit a country to the EU without knowing its parameters, this would be unprecedented”, he said, remarking: “I think we need to answer very long and difficult questions until we get to actually deciding about the start of accession talks.”

Hungary signalling its reservations is not without consequence. Certain key factors in the European Union work on the basis of unanimity: if a single European Union member state disagrees with allowing a new state to join, it cannot proceed, giving Hungary and any other state concerned about admitting an active warzone into the continent-wide bloc a total veto. Orbán also holds a similar veto over Ukraine’s ambitions to join NATO.

Hungary’s conservative government has condemned the Russian invasion, admitted Ukrainian refugees, and trained Ukrainian soldiers but has also resisted calls to offer direct military aid in a bid to slow the “escalation” of the conflict.

The Ukrainian government responded with a curt missive to Orbán’s comments on the question of their territorial integrity, restating their line that Russian invasion or not, the internationally recognised borders of the country have not changed.

Orbán’s comments came as Roberta Metsola, one of the European Union’s presidents, said this week there is “nothing off the table” to make getting Ukraine an EU member faster, saying she wanted formal talks to start before Christmas. “If [Kyiv] are going fast, we should match that speed”, she said.

The Union’s other two presidents have made such remarks. President Ursula von der Leyen said this year that “history is on the move” and “the future of Ukraine is in our Union”. Last year, she said of Ukraine: “Over time, they belong to us. They are one of us and we want them in.”

The third EU President, Charles Michel has also spoken of getting Ukraine into the European Union, albeit on a longer time frame, more typical of the joining process. He said in August: “We must set ourselves a clear goal. I believe we must be ready — on both sides — by 2030 to enlarge. This is ambitious, but necessary. It shows that we are serious… Integrating new members into our union won’t be easy. It will affect our policies, our programmes, and their budgets. It will require political reforms. And political courage.”