Russian President Vladimir Putin has insisted that Ukraine give up land for any peace deal to be possible / RUSSIAN PRESIDENTIAL PRESS OFFICE / AFP

Donald Trump's son-in-law and special envoy headed to the Kremlin Tuesday for high-stakes talks on Moscow's offensive in Ukraine, as Ukrainian President Volodymyr Zelensky called for an end to the fighting and a "dignified peace".

Jared Kushner and envoy Steve Witkoff were due to meet with Russian President Vladimir Putin after days of frenzied diplomacy from Florida to Geneva to Abu Dhabi left Washington "optimistic" it could help end Europe's bloodiest conflict since World War II. 

They are expected to present Putin with a new version of US plan to end the war, hammered out in recent days after an earlier version raised fears in Kyiv and elsewhere in Europe that it made too many concessions to Moscow.

A Ukrainian delegation could then meet with Witkoff and Kushner as soon as Wednesday, potentially in Brussels, a senior Kyiv official told AFP. 

The US wants to "report directly to us after their meeting" with Putin, Zelensky said during a visit to Ireland, where he is shoring up European support. 

But any plan must actually end the war -- for good -- and not just lead to a pause in the devastating fighting that began with Moscow's offensive in February 2022, he said.

"Our common task is to end the war, not just to achieve a pause in hostilities," Zelensky said, adding: "A dignified peace is needed."

Putin, however, appeared to threaten the opposite shortly before the US talks began.

"We are not planning to go to war with Europe, but if Europe wants to and starts, we are ready right now," he told reporters, accusing Europeans of obstructing US efforts to end the fighting.

In Brussels, NATO chief Mark Rutte said he was "confident" US efforts will "eventually restore peace in Europe".

- Russian pressure -

The US-Russia meeting comes at a critical point for Kyiv.

Russian forces have advanced fast in November in eastern Ukraine, and Kyiv has been rocked by graft scandals that ended with the resignation of its top negotiator -- Zelensky's right-hand man.

Moscow has also stepped up drone and missile attacks on Ukraine in recent weeks, with Zelensky accusing the Kremlin of trying to "break" his country.

Zelensky has said he still expects to discuss key issues with the US president, including on territory, and suggested Moscow's real motivation for the US talks was to ease Western sanctions.

Putin has demanded that Kyiv surrender territory Moscow claims as its own for any deal to be possible.

The diplomatic push comes as Kyiv said that fighting was ongoing in Pokrovsk, the eastern Ukrainian town that Moscow has tried to capture for months -- despite Moscow claiming one day earlier that it had successfully seized the town.

- Drone attacks escalate -

Putin ordered the full-scale military assault on Ukraine in February 2022 -- calling it a "special military operation". 

Kyiv and its European allies say the war is an unprovoked and illegal land grab that has resulted in a tidal wave of violence and destruction.

Tens of thousands of civilians and military personnel have been killed since the war began, while millions of Ukrainians have been forced to leave their homes.

Europe has worried that Washington -- which has backed Kyiv with funding and weapons -- and Moscow will strike a deal over its head or force Ukraine into making unfair concessions. 

The original 28-point US plan last month hewed so closely to Moscow's demands it prompted accusations that Russia was involved in drafting it -- which Washington denied.

Bloomberg had last month reported that Witkoff had helped coach Russian officials on how Putin should speak to Trump.

Much of the diplomacy in recent days has been aimed at giving greater weight to Ukraine's interests in any deal. 

Witkoff has met with Putin multiple times, but US media reported that it was the first time that Kushner -- who also helped broker the ceasefire between Israel and Hamas in Gaza earlier this year -- would join the talks with Putin.

The meeting comes after Russia escalated its drone and missile attacks on Ukraine throughout November, according to an AFP analysis. 

Moscow launched a total of 5,660 missiles and long-range drones at Ukraine last month, daily reports published by Kyiv's air force showed, marking a two percent increase over the previous month.

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