Ukraine and Russia are set to meet in Istanbul on Friday for their first direct peace talks in more than three years.
Ukraine's President Volodymyr Zelenskyy had travelled to Türkiye but said he would not attend the talks, after his Russian counterpart Vladimir Putin declined his calls for face-to-face negotiations.
Tens of thousands have been killed since Russia launched its military action in February 2022, and Moscow's army controls around a fifth of Ukraine's territory.
Istanbul hosts pivotal trilateral peace meetings as Türkiye brings Ukraine, Russia, and the US to the table in a renewed push for ending the war.
Here is what is known about the talks in Istanbul:
When are the talks?
A three-way meeting between Russian, Ukrainian and Turkish delegations was initially set for 0930 GMT, a source in the Turkish foreign ministry said Friday.
But officials said the exact timings appeared to be in flux.
Ahead of that, US Secretary of State Marco Rubio held an hour-long meeting with his Turkish and Ukrainian counterparts, Hakan Fidan and Andriy Sybiga, respectively. The Ukraine delegation head, Defence Minister Rustem Umerov, also attended.
Separately, Michael Anton, the State Department head of policy planning, was to meet the Russian delegation.
Putin last weekend proposed the talks for Thursday, but then the Kremlin spent several days refusing to say who would go or provide any details.
Russia showed up in Istanbul on Thursday with a relatively low-level delegation, prompting Zelenskyy to send a pared-down team that arrived on Thursday evening.
Who is expected to attend?
The Russian side is headed by Vladimir Medinsky, a hardline aide to Putin and ex-culture minister who was involved in the two countries' last direct negotiations, in 2022.
The Kremlin named three other negotiators—Deputy Foreign Minister Mikhail Galuzin, Deputy Defence Minister Alexander Fomin and Igor Kostyukov, director of Russia's GRU military intelligence agency.
Zelenskyy on Thursday criticised the level of Russia's representatives, saying it was a sign Moscow was not "serious" about negotiating an end to the war.
Top diplomats like Foreign Minister Sergey Lavrov or Kremlin foreign policy aide Yuri Ushakov—involved in previous talks with the United States—are not in Istanbul.
The Ukraine delegation will be led by Umerov, who has Crimean roots and was involved in several rounds of diplomacy involving Moscow, including the 2022 talks, prisoner exchanges and a 2022 Black Sea grain deal.
He will be joined by around a dozen deputy ministers and military officials, including Deputy Foreign Minister Sergiy Kyslytsya, Deputy Security Service Head Oleksandr Poklad and Deputy Chief of General Staff Oleksiy Shevchenko.
Washington's top diplomat also flew into Istanbul on Friday to throw his weight behind the talks, although he will not join them.
Where do the two parties stand?
Zelenskyy said his team had a mandate to discuss an unconditional ceasefire that Kiev, its allies, and Washington have been pushing for.
Russia has repeatedly rejected the proposal, insisting a whole range of questions have to be settled before a ceasefire can be agreed.
Beyond that, the fundamental differences between Kiev and Moscow are far from resolved.
Russia insists the talks address what it calls the "root causes" of the conflict, including the "denazification" and demilitarisation of Ukraine, two vague terms Moscow has used to justify the invasion.
It has also repeated that Ukraine must cede its territory occupied by Russian troops.
Kiev says it will not recognise its territories as Russian—though Zelenskyy has acknowledged Ukraine might only get them back through diplomatic means.
What are the expectations?
US President Donald Trump appeared to concede that progress in Istanbul was unlikely, saying there would be no movement towards ending the war until he met Putin.
Rubio also said he has no "high expectations" for the talks.
Moscow's top negotiator insisted he was ready to discuss "possible compromises" in Istanbul.
"Unfortunately, they are not taking the real negotiations very seriously," Zelenskyy told reporters after a meeting with Erdogan.
Why Türkiye?
NATO member Türkiye has sought to maintain good relations with both Ukraine and Russia since the conflict began, and has twice hosted talks on the war.
Representatives from Moscow and Kiev discussed an outline to end the war in Istanbul in March 2022.
But those talks broke down following Russia's retreat from the Kiev suburb of Bucha, where hundreds of civilians were found dead following a month-long occupation by Russian forces.
Moscow sees these talks as a "continuation" of those failed negotiations, Medinsky said Thursday.
Contact between the warring sides has been limited since, and mainly focused on humanitarian issues, such as prisoner exchanges and the repatriation of soldiers' remains.
