Nato leaders have said Ukraine still has “conditions” to meet before it can join the alliance in a move that has left Volodymyr Zelensky frustrated.
During a summit in Vilnius, the alliance agreed that Kyiv could fast-track the process of joining – a concession called for by the UK – but said “additional democratic and security reforms” were still required.
Before the communique was released, Mr Zelensky had expressed his disappointment with the agenda for the gathering in Lithuania, saying it was “absurd” and “unprecedented” that no timetable for his country joining was being set out.
Mr Zelensky said the delay was providing Russia with the “motivation to continue its terror”.
In comments made after the document was released on Tuesday, the Ukrainian leader appeared to suggest that he continued to be unhappy at Nato’s stance.
He said he wanted his faith in Nato to “become confidence” and questioned whether that was “too much to expect” for his citizens, who saw Russian president Vladimir Putin’s attack on their homeland pass the 500-day mark this week.
“Nato will give Ukraine security. Ukraine will make the alliance stronger,” Mr Zelensky tweeted.
Prime Minister Rishi Sunak told reporters on his way to eastern Europe that he wanted to see Nato’s commitment to inducting Ukraine as a full member of the alliance “reaffirmed” during the two-day gathering.
Nato signalled at its 2008 summit in Bucharest that Kyiv should become a member state.
Mr Sunak repeated his stance that, for the UK, Ukraine’s “rightful place is in Nato”.
The statement agreed by the 31 member states did make that reaffirmation.
It also agreed with the UK’s stance that the membership action plan, part of Ukraine’s route to joining, would no longer have to be fulfilled.
The communique said Ukraine had “become increasingly interoperable and politically integrated with the alliance, and has made substantial progress on its reform path”.
A UK Government source said the fast-track decision was also a recognition that latest member Finland, along with Sweden which is due to join, did not have to undergo the plan.
But Nato said, despite Ukraine’s armed forces being honed on the battlefield in its struggle against the Kremlin’s invading troops, there was still more to do, both democratically and in military terms, before it could be permitted to join.
“Allies will continue to support and review Ukraine’s progress on interoperability as well as additional democratic and security sector reforms that are required,” Nato said in a joint statement.
“The alliance will support Ukraine in making these reforms on its path towards future membership.
“We will be in a position to extend an invitation to Ukraine to join the alliance when allies agree and conditions are met.”
Defence Secretary Ben Wallace said there were “some steps that need to be met” before the door can be opened to Mr Zelensky and his countrymen, with Nato calling for military improvements.
But the Cabinet minister said “we should be prepared as quickly as possible to bring Ukraine closer” once the conflict is over.
He told US broadcaster CNN: “We can see right now that its military is up to standard.
“Its military is taking on a far superior sized Russian force and has dealt them a heavy defeat.
“So I think overall, Ukraine is not far off membership.”
There has long been an acceptance that, due to the Article 5 clause that means all members would act to defend an ally, Kyiv cannot be admitted to Nato while it is at war with Moscow.
Its closest backers, however, had been keen to see a blueprint laid out for when Ukraine might be able to become the 33rd member.
Talks have instead moved to how a non-Nato alliance, without the Article 5 commitment, can support Ukraine in the long-term against Russian aggression.
Mr Sunak and allies are widely expected to use the summit to unveil fresh proposals to give multi-year backing to Kyiv’s forces.