Fighting in Eastern Ukraine intensified today, a day after a peace deal was reached in Minsk.
The fiercest battles were over control of the town of Debaltseve, a strategic town in between rebel-held areas.
The group responsible for monitoring the ceasefire, due to start at midnight on Saturday, said there is still “quite serious live fire” in several areas.
European leaders have warned Russia that more sanctions will be placed on the country if the Minks agreement is not respected.
Luhansk also came under bombardment overnight and Russian TV reported it was some of the heaviest fighting there in months.
Ukraine’s army said the most ferocious fighting centered on Debaltseve, a railway junction where rebels have besieged government troops in a last-ditch effort to win the town.
“The enemy continues to build up forces in the main areas of the armed conflict. The most tense situation is near Debaltseve,” military spokesman Andriy Lysenko said.
On Friday, the Ukrainian military said eleven soldiers had died and 40 more wounded in the previous 24 hours, while rebels said seven civilians had been killed.
The new clashes came amid wider doubts about the peace deal agreed following marathon negotiations between the leaders of Russia, Ukraine, Germany and France.
Michael Bociurkiw, spokesman for the OSCE monitoring group, said they were hopeful the deal would be fully implemented, but said things on the ground remained very turbulent.
“We feel that the Minsk agreements are really the only available roadmap to a sustainable ceasefire. But now unfortunately… there’s quite serious live fire in areas like Luhansk, Debaltseve,” he said.
He also said monitors had witnessed “significant movements” of unmarked military vehicles and convoys.
Pro-Russian rebels signed the peace agreement but key issues remain to be settled.
Ukrainian President Petro Poroshenko warned that implementation of the cease-fire would be difficult.
A new round of EU asset freezes and travel bans against 19 Ukrainian separatists and Russians, which were put into place in response to deadly fighting in the city of Mariupol in January, will come into effect on Monday regardless of the latest deal.