Ukraine's military and Russia-backed separatist rebels have accused each other of continuing to mount attacks a week after a ceasefire was called.
Ukrainian security spokesman Colonel Andriy Lysenko said that one serviceman was killed and 40 wounded in attacks over the past day.
He did not state a total number of attacks, but said there were 10 mortar attacks on Ukrainian forces in the village of Shyrokyne on the fringes of the strategic port city of Mariupol.
Col Lysenko said rebels continued to move equipment toward Mariupol.
Concerns persist that rebels aim to seize the city which would aid establishing a land corridor between mainland Russia and the Russia-annexed Crimea peninsula.
The rebels claimed Ukrainian forces launched 15 shelling attacks overnight, including on parts of Donetsk, the largest rebel-controlled city.
An agreement reached by the leaders of Ukraine, Russia, Germany and France called for the guns to go quiet on Sunday.
The warring sides were supposed to begin drawing back heavy weapons from the front lines on Tuesday, but international monitors say they have seen no sign of that yet.
Russian and Ukrainian military officials overseeing the hoped-for peace process announced yesterday that the Ukrainian government and the rebels had worked out a plan to begin the weapons pull-out.
Heidi Tagliavini, an envoy for the Organisation for Security and Co-operation in Europe (OSCE) who led the talks with Russia and Ukraine that also included rebel figures, remained cautiously hopeful.
"There is not a single day in the Ukrainian conflict when we can feel sure what the next day will bring," she said.