Ukraine's President Volodymyr Zelensky has given a positive assessment of a conversation he had with US envoys on how to end the Russia-Ukraine war.

Zelensky said Thursday's call with Steve Witkoff and Jared Kushner, which lasted nearly an hour, had yielded "new ideas in terms of formats, meetings, and... timing on how to bring a real peace closer".

He spoke a day after giving details of an updated 20-point peace plan, agreed by US and Ukrainian envoys in Florida.

Zelensky said he had asked Witkoff and Kushner to pass along Christmas greetings to US President Donald Trump "and the entire Trump family".

The Kremlin said it was analysing proposals brought back from the US by a Russian envoy.

Trump and his envoys have been holding talks with both Ukraine and Russia in an effort to reach a deal to end the war which was started by Russia's full-scale invasion of Ukraine in February 2022.

There appears to have been some progress in recent days with Ukraine's president praising the "good ideas" put forward by Witkoff and Trump's son-in-law Kushner.

Zelensky said it had been an "active day" for his country's diplomacy, as he went into details with the US envoys.

He conceded that there was still "work to be done on sensitive issues" but added that "together with the American team, we understand how to put all of this in place".

Zelensky added that Ukraine's top negotiator Rustem Umerov, the country's top security official, "will continue discussions with the American team".

The 20-point peace plan agreed by the US and Ukraine is seen as an update to the initial draft prepared by Witkoff several weeks ago.

That draft was widely seen as heavily geared towards Russia's maximalist pre-invasion demands, which Kyiv and its European allies said would mean the de facto capitulation of Ukraine.

Describing the updated proposal on Wednesday, Zelensky had said it offered Russia the potential withdrawal of Ukrainian troops from the east and the creation of a demilitarised zone in their place.

He said the plan now included security guarantees from the US, Nato and Europeans for a co-ordinated military response if Russia invaded Ukraine again.

On the key question of Ukraine's industrial eastern Donetsk region, Zelensky said a "free economic zone" was a potential option. Any area that Ukrainian troops pulled out of would have to be policed by Ukraine, he stressed.

Moscow currently controls about 75% of the Donetsk region, and some 99% of the neighbouring Luhansk. They are collectively known as Donbas.

Zelensky has been under heavy pressure from Trump to cede all of Donbas to Russia during ongoing Washington-led peace negotiations.

The Ukrainian leader has so far rejected any territorial concessions, and instead demanded iron-clad security guarantees for Ukraine in any potential settlement.

Russian President Vladimir Putin has repeatedly warned that Ukrainian troops must leave Donbas or Russia will seize it.

On Thursday, Kremlin spokesman Dmitry Peskov said Moscow was studying the proposals brought back from the US by the Russian envoy, Kirill Dmitriev.

"We are examining this material, and depending on the decisions made by the head of state, we will continue our communication with the Americans," he said.

While diplomatic efforts to end the conflict inch forward, fighting continues on the ground.

The Ukrainian military said on Thursday that it had struck one of Russia's key oil refineries in the southern region of Rostov with cruise missiles.

The Novoshakhtinsk refinery near the Ukrainian border is critical for supplying fuel for Russian military operations in occupied eastern Ukraine.

The Russian defence ministry said its forces had taken control of the settlement of Sviato-Pokrovske in the Donetsk region.

Earlier this week, Ukrainian troops withdrew from the embattled eastern town of Siversk.

The capture of the town brings Russia closer to the last remaining "fortress belt" cities of Sloviansk and Kramatorsk still in Ukrainian hands in the Donetsk region. (BBC)

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