The country was given candidate status after it applied for membership days after the Russian invasion in February, with the process since moving at a record speed.
Now the Ukrainian ambassador to the EU has said she is "100%" certain all 27 EU nations will approve making Ukraine a candidate for membership in the bloc during a summit this week.
In an interview with The Associated Press (AP), deputy prime minister for European and Euro-Atlantic integration, Olha Stefanishyna, said the decision could come as soon as Thursday, on the first day of the two-day EU leaders summit in Brussels.
Asked how confident she is that Ukraine will be accepted as an EU candidate, she said: "The day before the summit starts, I can say 100%."
Countries that had been sceptical - Ms Stefanishyna cited the Netherlands, Sweden and Denmark - about starting accession talks with Ukraine while it is fighting Russia's invasion are now supportive, she said.
The EU's executive arm threw its weight behind Ukraine's candidacy last week.
Ms Stefanishyna described that decision as "a game-changer" and said unanimous support from the European Commission had cut ground from under "the legs of those most hesitating - not even sceptic - but hesitating countries".
"Most of the EU leaders have explained that there is a consensus already, so there's no like, no discussion about the consensus on Ukraine," she told The AP.
EU leaders are to meet on Thursday to discuss the situation with Ukraine’s membership.
Candidate status is the first official step towards EU membership and France said this week there was "total consensus" on Ukraine. But it can take many years to join and there's no guarantee of success.
The Western Balkan countries of Albania, North Macedonia, Montenegro and Serbia have been candidate countries for years; in some cases for over a decade. Bosnia and Herzegovina applied for candidacy in 2016 but has still not succeeded.
In an update on the situation in Ukraine, the Ministry of Defence said that Russian advances around Donetsk Oblast remain stalled due to lack of advances in built up areas, troop movement and an inability to encircle the area.
The update from the MoD read: “Since 19 June, Russian forces have highly likely advanced over 5km towards the southern approaches of the Donbas city of Lysychansk.
"Some Ukrainian units have withdrawn, probably to avoid being encircled. Russia’s improved performance in this sector is likely a result of recent unit reinforcement and heavy concentration of fire.
"Russian forces are putting the Lysychansk-Sieverodonetsk pocket under increasing pressure with this creeping advance around the fringes of the built-up area. However, its efforts to achieve a deeper encirclement to take western Donetsk Oblast remain stalled.”
Russian forces have captured three villages in the heavily contested eastern region of Ukraine, a local official said. Governor Serhiy Haidai told The AP on Wednesday that the villages are a few miles from the city of Lysychansk, the last city in the area still fully under Ukrainian control. The Russians have also taken a strategic coal village, Toshkivka, enabling them to intensify attacks, Mr Haidai said.