Ukraine says that intensified fighting against Russia-backed separatists has left nine servicemen dead and 29 wounded over the past day.

Armed forces spokesman Vladislav Seleznyov said Tuesday that some of the fiercest fighting was around the town of Debaltseve, where separatists were attacking from two sides in an attempt to surround the Ukrainian forces.

Debaltseve is a road and railway hub to the northeast of Donetsk, the main rebel-held city in eastern Ukraine.

A lull in the fighting in December had raised hopes for a peaceful settlement, but hostilities have escalated again in recent weeks as the rebels launched a series of new offensives.

Russia has blamed the renewed fighting on the Ukrainian side, accusing it of trying to settle the conflict by force.