Russia's Vladimir Putin spurned a challenge to meet face-to-face with Ukrainian President Volodymyr Zelensky in Turkey on Thursday, dealing a blow to prospects for a peace breakthrough.
The Russian president dispatched a second-tier team of aides and deputy ministers to take part in talks in Istanbul, while US President Donald Trump, on a tour of the Gulf, undercut the chances of major progress when he said there would be no movement in the absence of a meeting between himself and Putin.
Zelensky said Putin's decision not to attend but to send what he called a "decorative" line-up showed the Russian leader was not serious about ending the war.
He said he himself would not go to Istanbul, but would send a team, headed by his defence minister, with a mandate to discuss a ceasefire. It was not clear when the talks would actually begin.
"We can't be running around the world looking for Putin," Zelensky said after meeting Turkish President Tayyip Erdogan in Ankara.
"I feel disrespect from Russia. No meeting time, no agenda, no high-level delegation - this is personal disrespect. To Erdogan, to Trump," Zelensky told reporters.
Erdogan told Zelensky that Turkey was ready to host him and Putin for peace talks "when they are ready", his office said.
In a statement, the presidency said Erdogan stressed the need to keep dialogue channels between the sides open given the "historic opportunity" to start peace talks, and that they should meet on their minimum common ground.
Zelensky backs an immediate, unconditional 30-day ceasefire but Putin has said he first wants to start talks at which the details of such a truce could be discussed.
More than three years after its full-scale invasion, Russia has the advantage on the battlefield and says Ukraine could use a pause in the war to call up extra troops and acquire more Western weapons.
Both Trump and Putin have said for months they are keen to meet each other, but no date has been set.
Trump, after piling heavy pressure on Ukraine and clashing with Zelensky in the Oval Office in February, has lately expressed growing impatience that Putin may be "tapping me along."
"Nothing's going to happen until Putin and I get together," Trump told reporters aboard Air Force One.
The diplomatic disarray was symptomatic of the deep hostility between the warring sides and the unpredictability injected by Trump, whose interventions since returning to the White House in January have often provoked dismay from Ukraine and its European allies.
While Zelensky waited in vain for Putin in Ankara, the Russian negotiating team sat in Istanbul with no one to talk to on the Ukrainian side.
Some 200 reporters milled around near the Dolmabahce Palace on the Bosphorus that the Russians had specified as the talks venue.
Trump said on Thursday he would go to the talks in Turkey on Friday if it was "appropriate".
"I just hope Russia and Ukraine are able to do something. It has to stop," he said.
Russia accused Ukraine of "trying to put on a show" around the talks. Its lead negotiator said the Russians were ready to get down to work and discuss possible compromises.
Asked if Putin would join talks at some future point, Kremlin spokesman Dmitry Peskov said: "What kind of participation will be required further, at what level, it is too early to say now."
Russia said on Thursday its forces had captured two more settlements in Ukraine's Donetsk region.
A spokeswoman for Russian Foreign Minister Sergei Lavrov pointedly reminded reporters of his comment last year that Ukraine was "getting smaller" in the absence of an agreement to stop fighting.
French Foreign Minister Jean-Noel Barrot said Zelensky had shown his good faith by coming to Turkey but there was an "empty chair" where Putin should be sitting.
"Putin is stalling and clearly has no desire to enter these peace negotiations, even when President Trump expressed his availability and his desire to facilitate these negotiations," he said.
Agencies