US President Donald Trump and his Russian counterpart Vladimir Putin will not attend what could be the first direct peace talks between Moscow and Kyiv in three years on Thursday, the Kremlin sending instead a group of experienced technocrats.

Putin on Sunday proposed direct negotiations with Ukraine in Istanbul on Thursday “without any preconditions”. Late on Wednesday, the Kremlin said the delegation would include presidential adviser Vladimir Medinsky and Deputy Defence Minister Alexander Fomin.

After the Kremlin's delegation announcement, a US official said Trump would not attend - days after saying that he was considering the trip.

While Putin had never confirmed he would attend in person, the absence of the Russian and US presidents lowers the expectations for a major breakthrough in the war that Russia started in February 2022.

Ukrainian President Volodymyr Zelenskiy had challenged the Kremlin leader to attend the talks “if he's not afraid,” in an apparent contest to show Trump who wants peace more. Zelenskiy was on his way to Turkey, a Ukrainian official said. Earlier, the Kyiv leader has said he would take part in the negotiations only if Putin were there.

Trump wants the two sides to sign up to a 30-day ceasefire to pause Europe's biggest land war since World War Two, and a Russian lawmaker said on Wednesday there could also be discussions about a huge prisoner of war exchange.

Zelenskiy backs an immediate 30-day ceasefire, but Putin has said he first wants to start talks at which the details of such a ceasefire could be discussed.

MORE SANCTIONS ON RUSSIA?

Trump, who is growing increasingly frustrated with both Russia and Ukraine as he tries to push them towards a peace settlement, said he was “always considering” secondary sanctions against Moscow if he thought it was blocking the process.

US officials have spoken about possible financial sanctions as well as potential secondary sanctions on buyers of Russian oil.

A Ukrainian diplomatic source told Reuters on Wednesday that Ukraine's leadership would decide on its next steps for peace talks in Turkey once there was clarity on Putin's participation.

The US delegation to Turkey included Secretary of State Marco Rubio and senior envoys Steve Witkoff and Keith Kellogg.

Ukrainian Foreign Minister Andrii Sybiha said early on Thursday he had met with Rubio to share Zelenskiy's peace vision and “coordinate positions during this critical week.”

Medinsky and Fomin, part of the Russian delegation, took part in the last set of negotiations between the two sides in the first weeks of the war.

Direct talks between negotiators from Ukraine and Russia last took place in Istanbul in March 2022, a month after Putin sent tens of thousands of troops into Ukraine in what he calls a “special military operation” to root out neo-Nazis.

Ukraine and its allies say the invasion was an unprovoked, imperial-style land grab.