Talks between Ukraine and Russia are due to get underway shortly after they met on the Belarussian border.
Ukrainian delegates are looking for an immediate ceasefire and the withdrawal of Moscow's troops from the country.
The United Nations says more than 100 civilians have now been killed in the conflict.
They have called two emergency meetings to discuss the ongoing conflict.
President Putin has put his nuclear weapons on high alert - but the UK defence secretary says that is partly a distraction tactic.
