Russian and Ukrainian negotiators began talks in Istanbul on Tuesday, and Turkish President Tayyip Erdogan told them that progress would pave the way for a meeting of the countries' two leaders since the time had come for concrete results.
In a televised speech to the negotiators ahead of their first discussions in more than two weeks, Erdogan called for an immediate ceasefire in the war that began last month when Russia invaded Ukraine.
"It is up to the sides to stop this tragedy. Achieving a ceasefire and peace as soon as possible is to the benefit of everyone. We think we have now entered a period where concrete results are needed from talks," he said.
"The negotiating process, which you have been carrying out under the orders of your leaders, has raised hopes for peace."
The Ukrainian embassy in Ankara said the delegation heads had begun talks and discussions would follow between the full delegations.
Foreign Minister Dmytro Kuleba said on Monday Ukraine's most ambitious goal at the Turkey talks this week was to agree a ceasefire. A senior U.S. official said Russian President Vladimir Putin does not appear ready to make compromises to end the war.
NATO member Turkey shares a maritime border with Ukraine and Russia in the Black Sea, has good ties with both and has offered to mediate the conflict. While calling Moscow's invasion unacceptable, Ankara has also opposed the Western sanctions.
Cardinals are scheduled to meet on Tuesday to plan Pope Francis' funeral, which leaders from around the world will attend ahead of a conclave next month to elect a new head of the Roman Catholic Church.
Russian President Vladimir Putin proposed on Monday bilateral talks with Ukraine for the first time since the early days of the war, and his Ukrainian counterpart Volodymyr Zelenskyy said Kyiv was eager to discuss a halt to attacks on civilian targets.
Pope Francis, the first Latin American leader of the Roman Catholic Church, died on Monday after suffering a stroke and cardiac arrest, the Vatican said in a video statement.
Ukraine issued air raid alerts for Kyiv and the country's eastern half as blasts shook the city of Mykolaiv early on Monday, authorities said, hours after the one-day Easter ceasefire declared by Russian President Vladimir Putin came to an end.
US Vice President JD Vance began a four-day visit to India on Monday and will hold talks with Prime Minister Narendra Modi, as New Delhi rushes to avoid steep US tariffs with an early trade deal and boost ties with the Trump administration.