Serhiy Cherevatyi, spokesperson for the eastern military command, told Ukrainian television that Ukrainian forces had not allowed Russian forces to break through front lines.
"The town is not under the control of the Russian Federation. There are fierce battles going on now," he said. "There is a complicated situation there."
He said the military command was "working now on how to stabilise the situation with the maximum impact for the enemy and minimum losses for Ukraine."
Russian mercenary group Wagner has said it has taken control of Soledar, a salt-mining town near the city of Bakhmut where fighting has also been fierce as Russia tries to capture the entire Donbas region of eastern Ukraine.
"The intensity of battles near Bakhmut can be compared with World War Two," Cherevatyi said.
Reuters was unable to independently verify the situation on the ground in Soledar.
Cherevatyi said Russian forces still had a lot of Soviet-era weapons and were using Soviet-era armoured vehicles with some modernised elements.
"Our partners are providing us with more modern weapons," he said, adding that Western weapons were more precise and gave Ukraine an advantage.
(Reporting by Olena Harmash, Editing by Timothy Heritage)
