The Ukrainian military said the battle for the town of Soledar continue as Russian forces try to advance in several parts of the eastern Donetsk region.
The General Staff of the Armed Forces of Ukraine said late Saturday local time that "the enemy does not abandon its intentions to completely take over Donetsk region."
"To do so, it focuses its main efforts on offensive operations on Bakhmut direction. Heavy battles for Soledar continue," the military said.
"Ukrainian forces repel enemy attacks round the clock. The occupiers suffer heavy losses," the General Staff said.
"The enemy is also advancing on Lyman, Avdiivka, and Novopavlivka directions," it added.
Ukrainian forces recaptured Lyman at the end of September.
On Friday, Russia said its forces had taken Soledar following weeks of fierce fighting, but Ukraine has denied the claim.
The General Staff also said Russian units in parts of Donetsk were below strength because of recent casualties.
"The manning level of certain units of the 3rd separate motorized rifle brigade of the 1st army corps located in the vicinity of Horlivka (Donetsk region) remains low, up to 40 percent," it alleged.
In the south, according to the General Staff, the Russians are trying to strengthen their defense capabilities on the east bank of the Dnipro river in Kherson.
"The movement of personnel, weapons, military equipment, and ammunition is reported," the military said.