More than two dozen people have been killed in eastern Ukraine in only 24 hours as hopes of a ceasefire evaporate after peace negotiations in Belarus collapsed again.
13 government soldiers and at least as many civilians have been killed in eastern Ukraine’s separatist conflict.
Hopes of easing tensions have been dashed with Ukraine’s representative and separatist envoys accusing the other of sabotaging negotiations.
The main members of the so-called contact group - Ukrainian former president Leonid Kuchma, a Russian diplomat and an Organization for Security and Cooperation in Europe official - had met at a state residence in the Belarussian capital Minsk yesterday, where they were joined by two separatist officials.
The talks were said to have broken up with no conclusion, with the atmosphere described as not fruitful.
A police chief said 12 civilians were killed on Saturday by separatist artillery shelling of the Debaltseve, which lies to the northeast of Donetsk.
Ukraine's Defence Minister Stepan Poltorak said 15 Ukrainian soldiers were also killed and 30 wounded in clashes across the east.
Both sides have accused each other of deadly artillery and mortar strikes on civilian targets in the past two weeks.
Territory seized
The September Minsk peace plan called for tighter control of the joint Russia-Ukraine border, through which Kiev says Moscow is channelling fighters and equipment.
Much has changed on the ground, however, since September.
The separatists, who Kiev says are supported by Russian troops, have seized more than 500 sq km (193 sq miles) of territory.
Ukraine military spokesman Andriy Lysenko said in a briefing: "The toughest situation is in the Vuhlehirsk area where the terrorists are trying to seize the town and occupy positions to move forward and encircle Debaltseve."
Debaltseve is on the main road between Donetsk and the other big rebel-controlled city of Luhansk and is also on a vital rail route for goods traffic from Russia.
The rebels were also continuing to threaten Mariupol, a town of half-a-million in the southeast of the country on the coast, Mr Lysenko said.
More than 5,000 people have been killed in the Ukraine conflict since last April, which flared up after Russia annexed Crimea.
US Secretary of State John Kerry will visit Kiev on Thursday for talks with President Petro Poroshenko and other Ukrainian officials, the US State Department said.
Russia denies providing troops and support to help the separatists and supplying them with military equipment.
US and Western sanctions against Russia have led to the biggest crisis in Russia-West relations since the end of the Cold War more than 20 years ago.
