Russia and Ukraine will restart face-to-face peace negotiations on Monday, against a background of warnings that the situation in the besieged city of Mariupol is now "catastrophic". Ukrainian President Volodymyr Zelensky has said he is willing to compromise on several sensitive topics.
The two sides have not negotiated directly for weeks, but will hold three days of talks in Istanbul from Monday, according to David Arakhamia, a Ukrainian negotiator.
Previous rounds of talks have failed to end the war sparked by the Russian invasion, which is now in its second month.
About 20,000 people have been killed, according to Zelensky, 10 million have fled their homes and, despite Russian military setbacks, several cities are still coming under withering bombardment.
"Our goal is obvious -- peace and the restoration of normal life in our native state as soon as possible," Zelensky said in a late-night video message that also set out his negotiating red lines.
"Ukraine's sovereignty and territorial integrity are beyond doubt. Effective security guarantees for our state are mandatory," he said.
Zelensky had previously indicated he is "carefully" considering a Russian demand of Ukrainian "neutrality" and indicated he was willing to negotiate the future of Donbas at a later date.
"We understand that it is impossible to liberate all territory by force, that would mean World War III, I fully understand and realise that," he said.
For his part, Putin has avoided clearly defining the goals of his invasion, stating only that he wants to "demilitarise and denazify" but not occupy Ukraine.
Macron seeks humanitarian solution
Meanwhile, in the southern port city of Mariupol, about 170,000 civilians are encircled by Russian forces, with ever-dwindling supplies of food, water and medicine.
Ukraine's foreign ministry said the situation there was "catastrophic" and the assault from land, sea and air had turned the once-thriving city of 450,000 people "into dust".
France, Greece and Turkey are hoping to launch a mass evacuation of civilians within days, according to French President Emmanuel Macron, who has sought an agreement from Russian counterpart Vladimir Putin.
With Russia's much-larger military hampered by fierce Ukrainian resistance, the Istanbul talks will test whether battlefield setbacks have tempered Moscow's demands.
Moscow was recently forced to abandon its efforts to capture Kyiv, and -- according to Russian general Sergei Rudskoi -- focus on the "main goal" of controlling the eastern Donbas region.
The fate of Russian-occupied Donbas and Crimea, as well as fundamental disagreements about Kyiv's alignment with the West are again set to be the focus of negotiations.
