Ukraine authorities say at least 13 Ukrainian soldiers have been killed and 20 others wounded since peace talks with pro-Russian rebels collapsed on Saturday.
Ten civilians also died as a result of fighting in Ukraine’s Donetsk and Luhansk regions, partly controlled by separatists since last April. There has been no immediate word on rebel casualties.
The latest fighting erupted after peace envoys from both sides abandoned talks in Belarus, without progress toward a deal ending the nearly 10-month conflict.
A statement from the trilateral contact group trying to advance the talks said rebel envoys were not prepared to discuss implementation of a cease-fire and withdrawal of heavy weapons.
Instead, contact group representatives from Russia, Ukraine and the Organization for Security and Cooperation in Europe said rebel envoys pushed for revisions in the Minsk agreement that laid the groundwork for a truce in September.
That cease-fire has been repeatedly violated and collapsed completely last week when rebels announced the start of a new offensive designed to expand their territory.
In a related development, the New York Times reported Sunday that NATO's military commander, General Philip Breedlove, now supports providing defensive weapons and equipment to Kyiv. Quoting unnamed U.S. officials, the Times report said the administration is taking a fresh look at the issue of military assistance, even though President Barack Obama has made no decisions on providing lethal aid. Ukraine President Petro Poroshenko in November did ask for such assistance.
In December, Obama signed legislation authorizing $350 million dollars in lethal and non-lethal military aid to Kyiv. But a White House spokesman at the time said the president had misgivings about delivering lethal hardware - a move that many analysts say would be viewed by Russia as a major Western military provocation.
Sunday, President Obama said there has been no recognition by the Kremlin that it is in Russia's interests to resolve the issue over the long term.
He told CNN television that rebels are Russian-financed, Russian-trained and reliant on the Kremlin for military strategy. He said his administration will continue pressuring Moscow economically, while conveying to Russian President Vladimir Putin that diplomatic resolutions remain available.
The Ukraine conflict has killed more than 5,100 people since it erupted last April following Russia's annexation of the Crimean Peninsula.
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