The Ukrainian army has accused pro-Russia rebels of breaking a new ceasefire deal hours after it came into affect, saying the separatists killed one soldier and wounded another.
The military on Monday blamed the rebels for persistent shelling often with heavy weaponry in the country's east.
"The occupying forces continue to shell our positions on all fronts," said Leonid Matyukhin, the Ukrainian military spokesman, announcing the latest casualties.
But Eduard Basurin, the spokesman for the rebels' self-proclaimed Donetsk People's Republic, said the truce had largely held since it started at midnight.
"It is possible to say that there were almost no attacks," he told the AFP news agency.
The latest attempt to silence the guns in Ukraine was agreed after more than 30 people were killed in a sharp increase in violence in early February between government forces and Russian-backed separatists.
But the deal, announced on Saturday after the foreign ministers of Ukraine, Russia, Germany and France held talks in Munich, remained fragile.
Also on Monday, Germany criticised as "unacceptable" Russia's decision to recognise passports issued by the separatists in the eastern Luhansk and Donetsk regions.
"The recognition of travel documents of the self-declared, so-called people's republics of Luhansk and Donetsk undermines the unity of Ukraine," said Steffen Seibert, German Chancellor Angela Merkel's top spokesman.
"It directly contradicts everything that was agreed in Minsk [peace talks] and is therefore unacceptable."
France on Monday also denounced the move, with the country's foreign ministry saying during a regular press conference that "France regrets this decision".
It said Paris wanted Moscow to focus on using its influence over rebels in Ukraine to ensure application of the terms of a peace accord negotiated in Minsk, adding: "It is the only way of ensuring a lasting solution to the crisis in east Ukraine."
After drawing the criticism, the Russian foreign ministry said in a statement published on its website: "The order fully complies with international law, which does not prohibit the recognition of documents needed to implement the rights and freedoms granted by the authorities which are not internationally recognised."
It would also demand that Moscow honour the internationally brokered Minsk agreements aimed at bringing peace after 34 months of conflict, he said.