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

The attacks came hours after brief direct talks failed to make any progress on steps to end nearly three-and-a-half years of war.

Ukrainian drones hit Russia's Sochi resort while Russian forces bombarded Odessa's residential areas and historic Pryvoz market, hours after ceasefire talks collapsed.