Ukraine is set to be approved as an EU candidate at a Brussels summit on Thursday, after the European Commission gave the green light.
The European Council, made up of leaders of the 27 member states, is meeting in Brussels to decide whether Ukraine should be awarded “candidate status”.
The move would kickstart the lengthy process of Ukraine’s accession to the bloc, which could take years and is not guaranteed.
Ukraine applied for EU membership four days after Vladimir Putin announced he was launching a “special militiary operation” in the country on February 24.
The country’s ambassador to the EU told the BBC the move would be a psychological boost for Ukrainians.
But Vsevolod Chentsov said “real integration” would only begin once the war has finished.
Several EU states are backing Ukraine’s candidacy, but only if certain conditions are attached before accession such as judicial and anti-corruption reforms.
Mr Chentsov said some reforms could begin to take place while the country is under invasion.
However, he said it would be “logical” for bigger reforms to be undertaken once the situation becomes more stable.
Some EU diplomats have raised concerns that awarding Ukraine candidate status could offer false hope, when in fact the prospect of membership could be decades away or the conflict could last years.
Countries in the Western Balkans, such as Albania, North Macedonia, Montenegro and Serbia have been candidate countries for years. Bosnia and Herzegovina applied for candidacy in 2016 but has still not been granted it.
Some members states want to see Bosnia granted candidate status, although that is not expected to happen.
There are hopes North Macedonia and Albania may make progress towards becoming fully fledged EU members.
Ukraine’s envoy told the BBC it did “not accept the idea of the queue”.
“Every state has its road map, has its path. And if there is political will, if there is support of society [and] business operators to move forward to implement reform in a bold and fast way, why we should wait?”