The defence ministers of France, Britain, Germany, Italy and Poland addressed reporters after meeting for talks in Paris.

They acknowledged the challenges posed by the new administration of Donald Trump in the US -- which is seeking direct talks with Russia to end the war sparked by the Russian 2022 invasion of Ukraine -- while insisting Europe was ready to stand on its own feet.

"There is obviously a very broad consensus emerging... that the first of the security guarantees for Ukraine is obviously the Ukrainian army itself," Lecornu told reporters, ruling out any postwar "demilitarisation" of Ukraine.

"The word 'demilitarisation' is emerging, but it is not the case. On the contrary, the real guarantee of long-term security will be the capabilities that we will be able to give to the Ukrainian army," Lecornu, a top ally of President Emmanuel Macron, added.

Lecornu said that "at this stage, about fifteen countries have shown an interest in continuing this process," referring to proposed options for a "security architecture" with a view to a lasting ceasefire" in Ukraine.

He warned against seeing Ukraine's post-war security solely in terms of European troops who could be deployed there, repeatedly insisting that this was not an issue to be decided on now.

Polish Defence Minister Wladyslaw Kosiniak-Kamysz also welcomed a "real unity of the continent", referring to the threat from Russia.

In his view, it was a matter of "keeping Russia at a distance from all our states as much as possible, and to do that, we must help Ukraine".

- 'US engagement is essential' -

German Defence Minister Boris Pistorius said that, despite the rapid pace of change, the current situation could help Europe.

"I am convinced that if we act now, if we choose security in Europe over the nitty-gritty of national interest, we will emerge from this situation strengthened," he said.

UK Defence Secretary John Healey said Britain and its allies knew that "we must step up" and re-arm.

"We are looking to build a coalition," he said. "We are accelerating this work."

He added: "In the coming weeks you will see European allies coming closer together."

He also spoke of "decisive days in the push for peace in Ukraine", but added that after Tuesday's agreement between Ukraine and the US it was up to Russia to show it was serious.

"I say to President (Vladimir) Putin 'it is over to you now'. You said you wanted talks. Prove it. Accept the ceasefire, start negotiations, and end the war"

"Make no mistake: the pressure is now on Putin," he said.

The defence ministers spoke after Ukraine on Tuesday gave the nod to a US-backed plan for a 30-day ceasefire, at talks in Saudi Arabia.

They also released a joint statement saying they had decided to "remain committed to NATO as the cornerstone of collective defence."

"US engagement is essential in that regard," the joint statement said.

Ukraine's deputy defence minister, Serhii Boiev, took part in the meeting by video link, according to the statement.

Wednesday's meeting came after Macron on Tuesday called on military chiefs from across Europe and beyond to move "from concept to plan" and draw up a plan "to define credible security guarantees" for Ukraine in the event of a ceasefire, the Elysee said.

That rare meeting on Tuesday in Paris gathered representatives from 34 countries -- most of them from Europe and NATO, but also from Australia, New Zealand and Japan -- but excluded officials from the United States.