A Ukrainian delegation said Thursday it was en route for a second round of ceasefire talks with Russia on the day Ukraine lost its first major city to Russian forces.
"On our way to negotiations with the Russian Federation. Already in helicopters," presidential advisor Mykhailo Podolyak said on Twitter.
Podolyak posted a photo of himself with lawmaker David Arakhamia dressed in military uniform in what appears to be a helicopter cabin.
Arakhamia said on Facebook that Ukraine wants to negotiate humanitarian corridors with Russia.
"We start in two hours," he wrote at around 12:00 GMT.
Russia's delegation — led by President Vladimir Putin's aide Vladmir Medinsky — said its proposals have to do with "military-technical, humanitarian-international and political" aspects.
According to Belarus and Russia, the talks will take place in the Belovezhskaya Pushcha in Belarus's Brest region close to the border with Poland.
A first round of talks between Russian and Ukrainian delegations took place earlier this week on the Ukrainian-Belarusian border, but brought no results.
Ukraine demands an immediate ceasefire and the withdrawal of Russian forces.
Russia has not specified its demands, but says it wants "the demilitarisation and denazification" of its pro-Western neighbor.