Flags of European Union and Ukraine flutter outside EU Parliament building, in Brussels, Belgium, February 28, 2022.
Flags of European Union and Ukraine flutter outside EU Parliament building, in Brussels, Belgium, February 28, 2022. Reuters / YVES HERMAN

European Union leaders may discuss the possibility of Ukrainian membership at an informal summit in March, a senior EU official said on Monday, adding the issue was important for Ukraine in discussions with Russia on ending the conflict.

Ukrainian President Volodymyr Zelenskiy said on Monday that he had signed an official request for Ukraine to join the bloc.

"I think one of the reasons that this is important for President Zelenskiy is also potentially in some of the discussions with Russia on a way out," the official said referring to talks to end the conflict.

But he added that no process had been started yet.

"On the application (of Ukraine for EU membership) I think it's important not to get ahead of ourselves," the official, who asked not to be named, said.

"It obviously has not yet been received, but this whole question of the Ukraine situation is something that's very much on the minds of the leaders."

The bloc's top diplomat Josep Borrell said the immediate priority was to provide practical support to Ukraine to counter the Russia invasion, rather than discussing long-term issues which could take years.

"We have to provide an answer for the coming hours, not for the coming years," he told reporters on Monday when asked about Ukraine's membership of the EU.

"Ukraine has clearly a European perspective, but now we have to fight against an aggression."

The chairman of EU leaders Charles Michel and the head of the European Commission Ursula von der Leyen will meet French President Emmanuel Macron and German Chancellor Olaf Scholz in Paris on Monday evening for talks.

"So I'm sure this will come up in those discussions. And of course we have quite imminently, on the 10th and 11th of March, an informal European Council meeting and I would imagine that the Ukraine topic, which is occupying many leaders' minds, will feature at some point in those discussions," the official said.

Ukraine has an association agreement with the 27-nation bloc but wants to become a full member - something that Russia is opposed to. Ukraine's membership has so far not been discussed so as not to antagonise Moscow, but the Russian invasion of Ukraine has changed things, the official said.

"This unprecedented Russian aggression that we're seeing against Ukraine, the strong condemnation of this we've seen by the EU, the outrage in the European Union, member states, public opinion -- I think that is also likely to be a factor that will determine the way in which we respond (to a membership application)," the official said.

"If you go to the origins of some of this standoff, there were a large number of people who were prepared to lay down their lives for a European perspective that was at the heart of the Maidan demonstrations (in Kyiv in 2013-14)," the official said.

"I think in any agreement that President Zelenskiy may reach with President Putin, seeking assurances, or getting a guarantee if you like, that there is a support, understanding for Ukraine belonging one day to the European Union, is likely to be very important for the Ukrainian people," he said.

Slovenian Prime Minister Janez Jansa on Monday expressed "full support" for a speedier EU membership procedure for Ukraine, while Czech Prime Minister Petr Fiala said it was necessary to give a clear signal that Ukraine was welcome, CTK news agency cited him as saying on Monday.