Russian Foreign Minister Sergey Lavrov gave Ukraine an ultimatum on Monday to fulfill Moscow's proposals, including surrendering territory Russia controls, or its army would decide the issue, a day after President Vladimir Putin said he was open to talks.

Kyiv and its Western allies have dismissed Putin's offer to talk, with his forces battering Ukrainian towns with missiles and rockets and Moscow continuing to demand that Kyiv recognize its conquest of a fifth of the country.

Kyiv says it will fight until Russia withdraws.