One soldier was killed in shelling and another died after stepping on an IED, the army said in a statement.

A military doctor died when he was trying to evacuate the soldier killed in an explosion, the army said. Two other members of the team carrying out the evacuation were wounded.

On Sunday, six other Ukrainian troops were wounded on the frontline.

Kiev accused separatists of violating a ceasefire 11 times over the previous 24 hours and of firing 120 mm mortars that are banned under a peace accord drawn up in Minsk.

The recent upsurge in fighting was the bloodiest since March. Before that, there had been a prolonged period of calm following the election of President Volodymyr Zelensky in April last year, as he promised to bring a swift end to the conflict.

More than 13,000 people have died in the war and around 1.5 million people have been forced to flee their homes since the conflict broke out in 2014.

Peace agreements signed in 2015 greatly reduced the fighting but the two sides have made no progress towards a political solution.

Kiev and its Western allies accuse Russia of providing military aid to the separatists, which Moscow denies.