On Monday, the leaders of eight European Union nations in Central and Eastern Europe backed Ukrainian President Volodymyr Zelensky's call for the EU to expedite Ukraine's membership.

In an open letter, the leaders wrote: “We, the Presidents of the EU member states: the Republic of Bulgaria, the Czech Republic, the Republic of Estonia, the Republic of Latvia, the Republic of Lithuania, the Republic of Poland, the Slovak Republic, and the Republic of Slovenia strongly believe that Ukraine deserves receiving an immediate EU accession perspective."

During a briefing in Kiev, Zelensky had requested immediate membership into the Union as Russia began its special military mission in Ukraine. He appealed for membership in a "new special procedure," adding that "our goal is to be together with all Europeans and, most importantly, to be on an equal footing. I’m sure it’s fair. I'm sure it’s possible."

Days ago, the EU shot down his request and his hopes of the EU helping Ukraine were dashed.

Several officials walked back a comment by European Commission chief Ursula von der Leyen that appeared to hold out the prospect of Ukraine being admitted.

"They are one of us and we want them in," she told Euronews in an interview on Sunday, after emphasizing existing EU-Ukraine cooperation.

Zelensky seized upon that on Monday to appeal to the European Union "for the immediate accession of Ukraine via a new special procedure."

Usually, joining the EU is a lengthy and arduous procedure that entails adopting the bloc's rules and currency. Croatia was the latest country to join, with its application being formally accepted in 2013, ten years after it first applied.

EU 'sensitivities' 

In any event, the European Commission stated that it can only negotiate with potential candidate countries if it has acquired a mandate from the EU's 27 member states, which Ukraine has not received.

"At the end of the day, this is a debate at the highest political level, for the (European) Council," where the member states take decisions, said a commission spokeswoman, Ana Pisonero.

The president of the European Council, Charles Michel, revealed to a group of journalists that there were already longstanding disagreements among EU countries on enlarging the bloc.

"There are different opinions and sensitivities within the EU on enlargement," he told a group of journalists.

He mentioned that Kiev would have to submit an official request to join before member states - which would have to greenlight membership unanimously - could come up with a position.

Zelensky signed the request yesterday.