KYIV (AFP) — United States envoys Jared Kushner and Steve Witkoff arrived in Kyiv Sunday for their first visit to the Ukrainian capital, a day after holding talks with Russia's Vladimir Putin in the Kremlin on ending more than four years of war between the neighbors.

US President Donald Trump's business partner Witkoff and son-in-law Kushner had visited Moscow several times but had not held talks in Kyiv — hit by deadly Russian strikes since 2022.

They are due to meet with Ukrainian President Volodymyr Zelensky. An Agence France-Presse (AFP) reporter in Kyiv saw the American envoys arrive by train.

They are hoping to revive negotiations to end Europe's worst conflict since World War II, after a summer of escalation.

Moscow's invasion of Ukraine has killed hundreds of thousands of people and displaced millions.

Witkoff and Kushner met with Putin on Saturday to "advance President Trump's agenda of peace in the Russia-Ukraine War," a White House official said in a statement to AFP.

"The two sides discussed substantive plans for next steps, which will be announced in the coming weeks, and look forward to equally productive meetings tomorrow in Ukraine."

Kremlin aide Yuri Ushakov called the talks "extremely frank," saying the Americans "put forward a number of ideas on possible routes to a settlement," but did not elaborate.

The Russian side told the Americans that Moscow was "confident" it could achieve its military goals of seizing the rest of eastern Ukraine, Ushakov added.

Both Russia and Ukraine have vowed not to strike each other's capitals for three days to allow for the negotiations to take place.

It was Kushner and Witkoff's eighth visit to Moscow during the war — but it is their first in the Ukrainian capital, hit by deadly Russian strikes throughout the war.

Russia's TASS news agency reported early Sunday that Witkoff and Kushner had arrived in Rzeszow in Poland on their way to Kyiv.

Zelensky on Sunday said Ukraine was "ready for the conversation."

"Ukraine has always been and will remain constructive," the wartime leader said on social media ahead of their visit.

The country's airspace has been closed since Moscow launched the war in February 2022 and visiting leaders have been arriving by train.

For many Ukrainians, hopes of a breakthrough remain slim.

"At this point it doesn't give me any hope. There have already been too many negotiations," Yaroslav, a 29-year-old Kyiv resident, told AFP.

Putin thanks Trump

In televised comments before the talks, Putin said Russia would ensure the safety of the envoys in Kyiv — a city Moscow has pounded with deadly strikes throughout the war.

"We will do everything that depends on us to ensure the safety of the negotiation process and mediators such as yourselves," Putin told Witkoff and Kushner.

Earlier Saturday, Putin had thanked Trump for persisting in his efforts to end the war despite it being "not simple."

Of the envoys' trip to Kyiv, he said: "No matter what happens next, contacts of this kind are undoubtedly always beneficial."

Trump said on Friday his envoys were bringing a "proposal" to end fighting.

"We have an idea for peace," he said, without elaborating.

US efforts have so far not led to a breakthrough in the war, and peace efforts have stalled in part because of Washington's war with Iran.