Nato is considering plans to establish a €100 billion ($108 billion) five-year fund for Ukraine which would put the country on a more secure military footing in its war against Russia.
The bloc's foreign ministers are gathering in Brussels on Wednesday for a two-day meeting where they will discuss the proposals and mark the alliance's 75th anniversary on Thursday.
Secretary General Jens Stoltenberg's plan would give the alliance a more direct role in co-ordinating the supply of arms, ammunition and equipment for Ukraine.
The deal would also “Trump-proof” long-term military support for Kyiv ahead of the US presidential election in November, amid fears that the result will destabilise the alliance.
“We need to shift the dynamics of our support,” Mr Stoltenberg said as he arrived at the summit.
“We must ensure reliable and predictable security assistance to Ukraine for the long haul, so that we rely less on voluntary contributions and more on Nato commitments, less on short-term offers and more on multiyear pledges.”
The plan could be approved by members at the Nato meeting in Washington in July.
Polish Foreign Minister Radoslaw Sikorski said he supported Mr Stoltenberg's efforts and Canadian Foreign Minister Melanie Joly said she welcomed “any form of support that Ukraine can have”.
Mr Stoltenberg said ministers would discuss how Nato could assume more responsibility for coordinating military equipment and training for Ukraine.
He declined to confirm the €100 billion figure, which was leaked by several diplomats, but said the aim was for a decision to be taken at this summer's Nato summit.
Allies are still discussing Mr Stoltenberg’s proposal and any mechanics of the accounting, including whether to factor bilateral aid to Ukraine in to the overall sum, reports say.
Under the plans, Nato would also take over some military co-ordination work from a US-led ad hoc coalition, known as the Ramstein group.
Commenting on the meeting, Estonia's Foreign Minister Margus Tsahkna said his country had proposed to allies that each year they provide 0.25 per cent of their GDP in military support to Ukraine.
Latvian Foreign Minister Krisjanis Karins said it was a “very good proposal” as he arrived at the meeting, adding that the funds could be a percentage of each member's GDP.
US Secretary of State Antony Blinken, who will attend the Brussels meeting, said in Paris on Tuesday that Nato was looking at measures that could serve as the “necessary bridge” to membership of the alliance for Ukraine.
Nato has stated that Ukraine cannot join while it is at war with Russia but that it will become a member at some point.
“Ukraine will become a member of Nato. It is a question of when, not if,” Mr Stoltenberg said on Wednesday.
The meeting comes as Nato is seeking a new leader to succeed Mr Stoltenberg, who has been in post for nearly 10 years.
Dutch Prime Minister Mark Rutte has the backing of a some 90 per cent of Nato members for the job – including the United States, France, Britain and Germany.
But he faces opposition from Hungary – which objects to his criticism of Prime Minister Viktor Orban's government – and a late challenge from Romanian President Klaus Iohannis.
