"Naturally, no one expects an easy road. Naturally, this will be a very difficult conversation. The projects (of the two sides) are diametrically opposed," said the Kremlin spokesman.

The two sides agreed to have a prisoner exchange of 1,200 people, National Security and Defense Council Secretary Rustem Umerov said.

Russian President Vladimir Putin said that Moscow hoped for more peace talks with Ukraine but that the momentum of the war was in its favour, signalling no shift in his stance despite a looming sanctions deadline from Washington.