President Volodymyr Zelenskiy will attend talks on Ukraine this week only if Russia’s Vladimir Putin is also there, an aide to the Ukrainian leader said on Tuesday, challenging the Kremlin to show it is genuine about seeking peace.

U.S. President Donald Trump’s senior envoys, Steve Witkoff and Keith Kellogg, will travel to Istanbul for the talks on how to end Russia’s war in Ukraine, three sources familiar with the plans told Reuters.

Trump has offered to attend himself if necessary but a senior U.S. official said it was unclear whether anyone from the Russian government would show up. President Putin, who has questioned Zelenskiy’s legitimacy, has not said whether he will take part.

“President Zelenskiy will not meet with any other Russian representative in Istanbul except Putin,” Ukrainian presidential adviser Mykhailo Podolyak told Reuters.

Asked who would represent Russia at the talks, Kremlin spokesperson Dmitry Peskov said: “As soon as the president sees fit, we will announce it.”

Both Moscow and Kyiv have sought to show they are working towards peace after Trump prioritised ending the war, which has raged for over three years since Russia’s full-scale invasion of Ukraine in February 2022, but have yet to agree any clear path.

Putin on Sunday proposed direct talks with Ukraine, after ignoring a Ukrainian proposal for an unconditional 30-day ceasefire. Trump publicly told Zelenskiy to accept.

The Ukrainian leader then said he would be waiting for Putin in Istanbul on Thursday, though the Kremlin chief had never made clear he intended to travel himself.

CEASEFIRE EFFORTS

Reuters reported last year that Putin was open to discussing a ceasefire with Trump, but that Moscow ruled out making any major territorial concessions and demanded that Kyiv abandon ambitions to join NATO.

Ukraine has said it is ready for talks but a ceasefire is needed first, a position supported by its European allies.

Zelenskiy’s chief of staff, Andriy Yermak, said on Tuesday the Ukrainian president’s planned trip to Turkey showed Kyiv was ready for talks, but repeated Ukraine’s stance that any negotiations must come after a ceasefire.

“Our position is very principled and very strong,” Yermak told a conference in Copenhagen.

A senior Russian official, Deputy Foreign Minister Sergei Ryabkov, was quoted by Russian news agencies as saying Moscow was ready for serious talks on Ukraine but doubted Kyiv’s capacity for negotiations.

The agencies quoted him as saying realities “on the ground” should be recognised, including the incorporation of what Moscow calls “new territories” into Russia – a reference to territory in Ukraine that is occupied by Russian forces.

U.S. officials hope Russia will agree to a comprehensive 30-day land, air, sea and critical infrastructure ceasefire, a senior U.S. official told Reuters.

Kyiv has already agreed to abide by such a deal and a 30-day ceasefire is also backed by European nations, with the threat of more sanctions hanging over Russia if it does not also agree to a ceasefire.