French President Emmanuel Macron announced new steps to boost Ukraine in its fight against the Russian invasion, saying not even the sending of Western ground troops was ruled out to achieve Europe's goal of defeating Moscow.

Speaking on Monday after hosting a meeting of two dozen European leaders to discuss Ukraine, Macron painted a grim picture of a Russia whose positions he said were "hardening" both at home and on the battlefield.

"We are convinced that the defeat of Russia is indispensable to security and stability in Europe," he said.

Russia, he said, was showing a "more aggressive attitude not just in Ukraine but in general".

While there was "no consensus" on the sending of Western ground troops to Ukraine, "nothing should be excluded. We will do whatever it takes to ensure that Russia cannot win this war," he said.

He refused to say more about France's position, citing the need for "strategic ambiguity" but saying the issue was mentioned among the options". 

Slovak Prime Minister Robert Fico was quoted as saying some EU and NATO members were weighing the option.

"Many people who say 'never, ever' today were the same people who said 'never tanks, never planes, never long-range missiles' two years ago" when Russia invaded, said Macron. "Let us have the humility to note that we have often been six to twelve months late."

'More and quicker'

Macron said the new coalition would be set up to supply Ukraine with "missiles and bombs of medium and long range to carry out deep strikes".

There was a "broad consensus to do more and quicker", he added, saying there was also a consensus to ramp up joint production of armaments with Ukraine and boost its own military industry.

Czech Premier Petr Fiala meanwhile said there was "great support" for an initiative to help Ukraine buy munitions outside the EU. Dutch Prime Minister Mark Rutte said his country would contribute and others would follow. 

"Nothing can be excluded to achieve our objective. Russia cannot win that war," said Macron.

German Chancellor Olaf Scholz and Polish President Andrzej Duda were among around 25 European heads of state and government at the conference.

Other states sent ministers, with foreign secretary David Cameron in Paris for Britain, and the United States and Canada were also represented.

As he opened the conference at the Elysee Palace, Macron said that Ukraine's allies needed to jump-start their support as the war entered its third year.

"We have seen hardening on the part of Russia, especially these past few months," Macron said. 

He said this had "cruelly" manifested in the death on February 16 of President Vladimir Putin's top opponent Alexei Navalny, but also in a hardening of Russia's positions on the frontlines, where it was planning "new attacks".

Make a 'leap'

Macron said a "leap" was needed from the West in its approach that "takes into account the transformation of the threat from a military and strategic point of view".

The conference signalled Macron's eagerness to present himself as a European champion of Ukraine's cause, amid growing fears that American support could wane in the coming months.

"Together we must ensure that Putin cannot destroy our achievements and cannot expand his aggression to other nations," Ukrainian President Volodymyr Zelensky said in a brief video message to the conference.

Western officials acknowledge that Russia risks gaining the upper hand in the conflict this year as Ukraine runs out of weapons and ammunition.

Ukrainian Defence Minister Rustem Umerov said Sunday that half of the Western military aid pledged to Kyiv is delivered late, noting that "commitment does not constitute delivery".

Zelensky complained Ukraine only received 30 percent of a million shells the EU had promised. "It is clear that we did not have this million," Macron said, acknowledging an "imprudent commitment".

There are growing doubts about the viability of long-term US backing for Ukraine as a new aid package struggles to find legislative approval and Donald Trump, who has indicated opposition to further support for Kyiv, eyes a return to the presidency in elections this year.