Ukrainian servicemen of the 10th Mountain Assault Brigade 'Edelweiss' engage in fighting near Bakhmut, amid Russia's attack on Ukraine, in Donetsk region
Ukrainian servicemen of the 10th Mountain Assault Brigade 'Edelweiss' engage in fighting near Bakhmut, amid Russia's attack on Ukraine, in Donetsk region, Ukraine, in this screen grab taken from a social media video released on May 19, 2023. 10th Mountain Assault Brigade 'Edelweiss'/via REUTERS . Reuters

Ukraine said on Friday it had repelled attacks by Russian forces trying to recapture land they had lost around the devastated eastern city of Bakhmut, where Kyiv says it has inflicted heavy Russian casualties.

A Ukrainian mortar unit near the city told Reuters it had advanced this week, but was facing heavy fire from Russian forces who appeared to have significant strength in manpower and stocks of ammunition.

"The fire was intensive this week. Our forces pushed forward a little, stopped near the canal. It's hard to push them (the Russians) out of there," said a soldier with the call sign Medvid, which means "bear" in Ukrainian.

The unit's troops said they were firing around 100 mortar rounds a day at Russian positions. They said their location could not be disclosed.

Ukraine says it has made small advances this week on the flanks of the city in the industrial Donbas region even as Russia's Wagner private army has inched closer to capturing the city itself.

Deputy Ukrainian Defence Minister Hanna Maliar said the Russian forces had gained some ground inside Bakhmut in fierce fighting but did not control the city.

"The enemy is trying to regain what they have lost... but our forces are repulsing the attacks," she said in televised remarks. "It's very difficult to carry out combat missions there and every metre (of advance) is like 10 kilometres in other conditions."

She said the Russian forces had made "some progress" inside Bakhmut but did not say how far forward they had advanced.

The head of Russian mercenaries fighting in Bakhmut said the city was unlikely to fall in the next two days. Ukrainian soldiers, he said, were holed up in a makeshift "fortress" in the south of the city.

Moscow regards its assault on Bakhmut, a city of about 70,000 before Russia's full-scale invasion nearly 15 months ago, as an important part of a campaign to capture the rest of the industrial Donbas region of eastern Ukraine.

Ukrainian Defence Minister Oleksii Reznikov told Ukrainian news portal RBK that Russia had taken up to 70,000 casualties in and around Bakhmut including dead and wounded.

The assertion could not be independently verified. Russia says Ukraine has sustained heavy losses in the area.