Two Ukrainian servicemen were killed in attacks by Russian-backed separatist rebels in the east of Ukraine in the 24 hours up to Saturday morning despite an agreed cease-fire, the Kiev military said.
Clashes between government forces and separatists have fallen significantly in the past three weeks, raising tentative hopes of success for a peace plan to end a conflict that has killed more than 6,000 people.
But the Kiev military said rebel attacks were continuing to test the cease-fire across a wide area of the east including near Mariupol, on the Sea of Azov, one of the last big towns still held by the government.
"As a result of armed clashes we lost two Ukrainian service personnel and another seven received wounds," Kiev military spokesman Andriy Lysenko told a briefing.
"In the past 24 hours there were 44 [rebel] attacks including attacks on populated areas," Lysenko added.
Russia and Ukraine have also argued publicly over the next steps in implementing the peace deal agreed in February in Minsk, with Kiev pressing for elections under Ukrainian law to be held in regions where the rebels have set up "people's republics".
Russia dismisses accusations from Kiev and the West that it has sent troops to back the rebels.