NATO chief Mark Rutte says a "victory plan" presented by Ukrainian President Volodymyr Zelenksiy is a good signal but that he is not able to support it as a whole as things stand.
"It is of course a strong signal from Zelenksiy and his team that they designed this plan ... That doesn't mean that I here can say I support the whole plan, that would be a bit difficult because there are many issues that we have to understand better," he said.
Zelenskiy unveiled his much anticipated "victory plan" on Wednesday, calling on his allies to take urgent steps to bolster Ukraine at a precarious moment in a bid to end the war with Russia next year.
As Russian forces advance in the east and a bleak winter of power cuts looms, he told parliament his plan contained five main points that were in the hands of his allies, including an unconditional invitation to join the NATO military alliance now and weapons support.
In return, he offered a role to Ukraine's allies in developing the country's natural mineral resources and said Ukrainian troops could enhance the security of NATO and replace some of the US forces in Europe.
"Together with our partners, we must change the circumstances so that the war ends. Regardless of what (Russian President Vladimir) Putin wants. We must all change the circumstances so that Russia is forced to peace," he told MPs and top officials.
Zelenskiy, who has unrelentingly called for a "fair" end to the war, says his plan is needed to force the Kremlin to negotiate in good faith although he appeared to acknowledge in his speech that some allies view the war's end game differently.
"We hear the word 'negotiations' from partners and the word 'justice' much less often. Ukraine is open to diplomacy but honest (diplomacy)," he said.
His plan proposed establishing a "comprehensive non-nuclear strategic deterrence package" inside Ukraine to protect against threats from Russia and to destroy its military power.
He did not elaborate but said there was an additional secret addendum that he could not disclose.
NATO has said Ukraine is heading for membership but has stopped short of issuing an invitation.
The Kremlin said it was too early to comment in detail but that Ukraine needed to "sober up" and realise the futility of the policies it was pursuing.
Zelenskiy said he would travel to a summit of European Union leaders in Brussels on Thursday to present his plan.
He already met US President Joe Biden in Washington DC at the end of the September to discuss it.
In a subsequent whirlwind tour of Europe, he met the leaders of the United Kingdom, France, Italy and Germany and outlined his plan.
The speech was attended by his top military, intelligence and political brass as well as MPs, some of whom occasionally stood up to applaud, although it was panned by some lawmakers.
Oleksii Honcharenko said the plan looked "very unrealistic": "We put almost everything on our partners. And what demands do we make of ourselves?"
Roman Lozynskyi, an MP for Zelenskiy's party, said it looked "fantastical" but that such past requests - such as for F-16s or Storm Shadow missiles - had once seemed unrealistic but nonetheless yielded results.
Zelenskiy's speech sought to persuade the exhausted public that the war can be ended soon and to emphasise the importance of ordinary Ukrainians remaining united as war challenges pile up.
"We achieved and are achieving results in battles thanks to our unity. Therefore, please do not lose unity," he said.
Zelenskiy will attend a NATO defence ministers' meeting on Thursday, according to NATO's revised agenda published late on Wednesday.