The European Union's executive is expected to propose on Friday that Ukraine become a formal candidate for membership of the bloc, diplomats and officials say.
It is a significant political gesture to the country as it resists Russia's invasion.
The European Commission recommendation is set to be signed off at a 23-24 June summit in Brussels.
But for the 27 EU leaders attending the meeting, it may force an unwelcome moment of reckoning over the failure of the bloc's broader "enlargement" policy.
EU candidate status, sought by Ukraine since 2014 when protests in Kyiv toppled an unpopular pro-Russian president, would be a milestone in its path from a former Soviet republic towards a developed economy in the world's largest trading bloc.
Candidate status "is a correct solution from a moral, economic and security perspective," Romanian President Klaus Iohannis said alongside his French counterpart Emmanuel Macron at a military base in Romania today.
Mr Macron, Mr Iohannis, German Chancellor Olaf Scholz and Italian Prime Minister Mario Draghi could visit Kyiv tomorrow.
"Before the war, you had a couple of eastern European members that uttered the possibility of Ukraine, Moldova and Georgia having a European pathway, but you had big players always saying categorically no," a senior EU diplomat said.
"The philosophy has changed now," he added.
But with Moldova and Georgia also likely to get EU membership status if they fulfil certain conditions, the June summit in Brussels will be a high-profile reminder that EU states cannot agree on whether to bring other official candidates - Albania, North Macedonia, Montenegro, Serbia and Turkey - into the bloc.
According to five diplomats and officials, cementing Ukraine's candidacy risks unrealistic expectations about membership for a country at war and with endemic corruption.
They also said it was divisive at a time when the bloc is seeking unity over economic sanctions on Russia following its 24 February invasion of Ukraine.
Eastern countries strongly support giving Kyiv the status of an EU candidate, but France, the Netherlands, Denmark, Belgium and Portugal have misgivings.
Two diplomatic notes seen by Reuters show the disagreement.
A Danish document argues that: "Ukraine does not yet sufficiently fulfil the criteria" of what it takes to be an EU candidate in terms of democracy, human rights, respect for minorities and the rule of law.
A Lithuanian document says: "By defending their country, Ukrainians are defending European values, freedom and democracy."
A senior Ukrainian official told Reuters that some 25 conditions have been set out by Denmark and others for Ukraine to meet, although they are not legally-binding EU standards.
The official said a positive decision "would give strong morale boost to the Ukrainian people. They really need this."
