Ukrainian forces have recaptured a clutch of territory around the eastern war-battered town of Bakhmut but made no major advances on the southern front, the deputy defence minister said Monday.
Russia countered saying its forces were improving their positions in the eastern region of Kharkiv and holding Ukraine's forces at bay further south.
Kyiv launched a counteroffensive against Russian troops in June after stockpiling Western weapons and building up offensive infantry units but has conceded that progress has been slow.
"Another three square kilometres (1.1 square miles) have been liberated (around Bakhmut). In total, 43 square kilometres around Bakhmut have been liberated" since the offensive began, Ganna Malyar told state television.
Bakhmut, an industrial town that was once home to some 70,000 people, was captured by Russian forces this summer after months of costly fighting.
Ukrainian forces began pushing back immediately around its flanks and have also been pushing towards the southern city of Melitopol under Russian control.
"In the south, the situation has not undergone significant changes. Our defenders continue to advance in the Berdyansk and Melitopol sectors," Malyar said.
She later added that Ukrainian forces had had successes near Robotyne along the southern front in the Zaporizhzhia region.
Russia, in the defence ministry statement, said its forces were fending off Ukrainian attacks in the south near the village of Urozhaine, which Ukraine captured last week.
Ukraine's Foreign Minister Dmytro Kuleba told AFP last week that his country's forces will liberate all territory occupied by Russian forces regardless of how long it takes.
At the same time, Russian forces have been pushing back in the northeastern region of Kharkiv, where officials recently urged vulnerable residents to evacuate frontline regions.
Russia's defence ministry said Monday their forces had taken up improved positions in the region with the help of artillery and aerial forces.