LONDON: US President Donald Trump said a deal to halt the Ukraine war was `very close` on Wednesday but hit out at Ukrainian leader Volodymyr Zelensky over his refusal to formally cede Crimea to Russia.

Trump`s comments came as Vice President JD Vance warned that the United States would `walk away` unless Russia and Ukraine agree a peace deal, and as envoys from Washington, Kyiv and European nations gathered for downgraded talks in Britain.

US media has reported that Trump is ready to accept recognition of annexed land in Crimea as Russian territory, but Zelensky told journalists this week it was Ukrainian territory and recognising it as Russian `is against our constitution`.

`It`s inflammatory statements like Zelensky`s that makes it so difficult to settle this War,` Trump said in a post on Truth Social, add-ing that Zelensky`s remarks will do nothing but prolong the `killing field`.

He added: `We are very close to a Deal, but the man with `no cards to play` should now, finally, GET IT DONE.` Earlier, Vance told reporters in India that the US has `issued a very explicit proposal to both the Russians and the Ukrainians`.

`It`s time for them to either say `yes`, or for the United States to walk away from this process,` he added. Vance said land swaps would be fundamental to any deal.

`That means the Ukrainians and the Russians are both going to have to give up some of the territory they currently own,` he added.

The reports said the proposal was first raised at a meeting with European nations in Paris last week. But French President Emmanuel Macron`s office said on Wednesday that `Ukraine`s territorial integrity and European aspirations are very strong requirements for Europeans`.

The latest round of diplomacy comes after a fresh wave of Russian air strikes that shattered a brief Easter truce.

A Russian drone strike on a bus transporting workers in the southeastern city of Marganets killednine people and wounded at least 30 more, the Dnipropetrovsk regional governor said on Wednesday.

Ukrainian authorities also reported strikes in the regions of Kyiv, Kharkiv, Poltava and Odesa.

In light of the attacks, Zelensky called for an `immediate, full, and unconditional ceasefire`. In Russia, one person was reported wounded by shelling in the Belgorod region.

`Work for peace` UK Foreign Secretary David Lammy had been due to lead a meeting of foreign ministers in London on Wednesday but the talks were downgraded to `official level` a sign of the difficulties surrounding the negotiations.

Kremlin spokesman Dmitry Peskov told reporters that `it has not yet been possible to reconcile positions on any issues, which is why this meeting did not take place`.

US Ukraine envoy Keith Kellogg attended, as did Macron`s diplomatic adviser Emmanuel Bonne.

Lammy met his Ukrainian counterpart Andriy Sybiga and Defence Minister Rustem Umerov.

Zelensky aide Andriy Yermak also attended the London talks.-AFP