Russia said Monday its forces were striking parts of the eastern Kharkiv region retaken by Ukraine, vowing to continue its military action in the country.
It also said it saw no opening for talks with Kyiv, ruling out negotiations.
The defence ministry in its daily briefing said Russian air, rocket and artillery forces were "delivering precision strikes on units and reserves of the Ukrainian armed forces", including in the urban hubs of Kupiansk and Izyum.
Over the weekend, Ukraine claimed sweeping successes against Russian forces in the south and the east, including the cities of Izyum, Kupiansk and Balakliya.
Ukrainian armed forces said Monday they had recaptured more than 20 settlements in the past 24 hours amid a large counter-offensive.
Russia said Saturday it was pulling back troops from the Kharkiv region as part of a decision to "regroup" its forces.
"The special military operation continues and will continue until the objectives that were originally set are achieved," Kremlin spokesman Dmitry Peskov told reporters.
Asked about potential peace talks with Kyiv, Peskov said he saw "no prospects for negotiations".
Russia's defence ministry said Monday that its forces had also carried out strikes in the southern Kherson region, where Ukrainian forces have also been advancing.
It said more than 300 Ukrainian troops had been killed and up to 1,000 wounded in the previous 24 hours, but the claim could not be independently verified.
