Ukraine's army and separatist rebels appeared to be complying at least partially with their truce accord, saying they will start pulling back heavy weapons from the frontline after carrying out a prisoner exchange.
A senior pro-Russian rebel commander said on Sunday separatist forces were due to begin withdrawing heavy weapons from the front line in east Ukraine.
"The plan was signed last night ... Starting from today there are two weeks to withdraw heavy weapons," Interfax news agency quoted Eduard Basurin, a commander, as saying.
Ukrainian General Olexander Rozmaznin told the AFP news agency: "The papers have been signed to begin withdrawing heavy weapons all along the frontline."
The planned withdrawal is a sign rebels and government forces may be prepared to halt hostilities as part of an internationally brokered peace deal.
Fighting has eased in many areas since a ceasefire came into effect a week ago, but the truce was shaken by the rebel capture on Wednesday of the town of Debaltseve, forcing a retreat by thousands of Ukrainian troops.
Russian news agency TASS quoted Basurin as saying the pull-back was still being organised and that the actual withdrawal of weapons would begin on Tuesday.
Ukrainian military spokesman Andriy Lysenko said by telephone there was no confirmation yet as to whether the rebels had started pulling back their weapons.
A Reuters witness saw a 20-vehicle convoy of separatist military trucks with anti-aircraft missile systems and howitzers leaving Debaltseve in the direction of Donetsk.
Donetsk and Luhansk are the two major cities in eastern Ukraine controlled by the pro-Russia separatists and where much of the fighting has taken place.
On Saturday, government forces and rebels exchanged nearly 200 prisoners, one of the first moves to implement the peace deal reached on February 12 in the Belarusian capital Minsk after the French, German, Russian and Ukrainian leaders met.
Both sides continue to accuse each other of violating the ceasefire.
The Ukrainian military said rebels had launched 12 attacks on government troop positions overnight, using artillery and mortar fire.
The town of Pesky near Donetsk had seen the most intense fighting, while separatist groups had attempted to "storm" Ukrainian positions in Shyrokyne, east of the port city of Mariupol on the Sea of Azov, the military said on Facebook.
Kiev accuses the separatists of building up forces and weapons in Ukraine's southeast and has said it is braced for the possibility of a rebel attack on Mariupol.