The leaders of Ukraine, Russia, Germany and France have arrived in Minsk for a crunch peace summit aimed at ending 10 months of conflict in eastern Ukraine.
Ukrainian President Petro Poroshenko will come face-to-face with Russian leader Vladimir Putin for the first time since October in a four-way meeting with German Chancellor Angela Merkel and French President Francois Hollande.
The make-or-break summit is the climax of a frantic diplomatic push by Europe to try to thrash out a peace plan to halt fighting between Ukrainian forces and pro-Moscow rebels that has cost at least 5300 lives since April.
Kiev and the West accuse Putin of masterminding the bloody uprising and say the meeting is a last chance to prevent the broadening of the conflict.
The European duo will hold a trilateral meeting with Poroshenko to try to hammer out a common position ahead of the sit-down with Putin.
Poroshenko arrived first at the grandiose presidential palace in Minsk and was greeted by Belorussian leader Alexander Lukashenko.
Some 50 people were killed in fierce fighting across east Ukraine in the hours leading up to the summit, as the warring sides battled for ground to strengthen their hands at the negotiations.
US President Barack Obama has warned that he may start delivering arms to Ukraine if the summit fails to find a solution to the crisis.