Putin

'I hereby challenge Vladimir Putin to single combat. Stakes are Ukraine', tweets Musk

A day earlier, statements from Russian and Ukrainian officials suggested there could be positive results 'within days'

Facebook will temporarily allow posts that call for the death of President Vladimir Putin and Russian forces

Moscow says it is open to honest and mutually respectful dialogue with Washington

Authorities in Mariupol say they would make a second attempt to evacuate some of 400,000 residents

This is a terrorist appeal that is completely unacceptable, says foreign ministry

US and Russian armed forces have set up a new direct phone line to reduce the risks of 'miscalculation'

Dmytro Kuleba, however, did not give any evidence for his claim

Mariupol, the main port on the Sea of Azov, is surrounded and under heavy bombardment

Parliamentarian says US refusal to provide more protection against airstrikes 'dooms Ukrainians'