Ukraine and Russia's presidents joined French and German leaders in Minsk today for a crucial peace summit after dozens of people died in one of the bloodiest days in the 10-month Ukraine conflict.
President Francois Hollande, Chancellor Angela Merkel and Ukraine's Petro Poroshenko were to hold brief talks before meeting Russian President Vladimir Putin, whom they accuse of masterminding the conflict.
EU foreign policy chief Federica Mogherini said the talks would be a "turning point for good or bad", while Russia -- accused by the West of fomenting the war by pouring troops and weapons across the border -- voiced optimism.
Dozens of people were reported killed in the run-up to the summit, the climax of a frantic diplomatic push to prevent the worst East-West crisis since the end of the Cold War from escalating.
Germany said the meeting, the most intensive international push for an end to the bloodshed in the east of the former Soviet state, offered a "glimmer of hope, nothing more".
"Experts are working, there is noticeable progress," Foreign Minister Sergei Lavrov said in Moscow, although he signalled there would be no flexibility on Ukraine's demand that it be given back control of its border with Russia.
Poroshenko warned he could introduce martial law throughout the country if the Minsk talks failed to stop the war that has already claimed more than 5,300 lives.
Martial law would mark a grave escalation of the crisis, freeing up military resources for the fight in the east but also likely leading to the cutting off of foreign investment for cash-strapped Ukraine, including a vital IMF loan.
The pro-Western leader said he, Hollande and Merkel would speak "with one voice" to Russian President Vladimir Putin, whom they accuse of backing the rebellion.
"The key position is that we need an unconditional ceasefire," he said.
US President Barack Obama has warned Putin that Russia -- already under punishing EU and US sanctions -- would be made to pay if the talks fail.
The bloodletting has been relentless in recent weeks as the rebels have pushed deeper into government-held territory and Kiev forces have counter-attacked.
At least 48 people were reported killed in the last 24 hours, including 16 in a devastating rocket attack on Kramatorsk, the Ukrainian government's eastern military headquarters and administrative hub.
