KIEV (AFP) - Both Ukraine and pro-Russian rebels on Saturday pledged to respect a ceasefire due to come into force within hours, after fierce fighting plunged the truce into doubt.
Under a peace plan signed between Kiev and the rebels in Minsk this week, the ceasefire is scheduled to start in war-torn east Ukraine at 2200 GMT on Saturday (6am on Sunday, Singapore time).
The agreement followed marathon talks between the leaders of Ukraine, Russia, Germany and France.
Ukraine's President Petro Poroshenko made the pledge in a phone conversation with German Chancellor Angela Merkel and French President Francois Hollande, the French presidency said in a statement.
"The Ukrainian President assured that everything was ready for the start of the ceasefire," it said.
Poroshenko's office also released a statement after the phone call saying that the three leaders agreed that "all sides, including Russia, must fulfil the obligations they have taken on themselves, most of all the ceasefire".
On the other side, rebel leader Alexander Zakharchenko - who Kiev and the West see as a Kremlin puppet - signed an order commanding his troops to observe an "immediate and total ceasefire" at the agreed time.
The order did, however, give the rebel forces the right to respond to any perceived attacks "with all force and means".
A senior rebel figure for the smaller self-proclaimed Lugansk People's Republic also insisted that they troops would obey the truce and pull back heavy weapons.
Under the terms of the peace deal the two warring sides have two days from the start of the truce to start pulling back heavy weapons from the front line.
The last-ditch peace plan is seen as the best hope of ending the violence that has claimed at least 5,480 lives since April but scepticism remains high after the collapse of a similar previous deal.
Ferocious fighting raged in the hours before the ceasefire was set to come into effect, with Ukraine and the United States accusing Russia of piling in weapons to fuel a rebel onslaught to grab territory.