Russia said on Friday that its forces had taken control of the salt-mining town of Soledar in eastern Ukraine, claiming to have made its first big battlefield gain after half a year of military setbacks.

Russian forces captured the town, long the focus of heavy fighting and bombardment, on Thursday evening, the defense ministry said.

It said this would make it possible to cut off Ukrainian supply routes to the larger town of Bakhmut, to the southwest, and trap remaining Ukrainian forces there.

Reuters was not able to immediately verify Russia's claim, which came after days of silence from the ministry about the fate of the town.

The head of Russian mercenary group Wagner had said on Wednesday that his forces had achieved the complete "liberation" of the mining town of Soledar, a claim denied by Ukrainian President Volodymyr Zelenskyy who said fighting continued.

"The capture of Soledar was made possible by the constant bombardment of the enemy by assault and army aviation, missile forces and artillery of a grouping of Russian forces," Moscow's defense ministry said.

Ukraine said earlier on Friday that its forces were still holding out in Soledar after a "hot" night of fighting, in what has become one of the bloodiest battlefields of the entire war.

Both sides have endured heavy losses in the battle for the small town.

Moscow has been seeking its first major victory after half a year of humiliating retreats. Kyiv says Russia is throwing wave upon wave of soldiers into a pointless fight for a bombed-out wasteland.

U.S. officials said a Russian victory in Soledar, or even in Bakhmut, a city ten times larger where the Russians have so far been repelled, would mean little for the overall trajectory of the war.

"Even if both Bakhmut and Soledar fall to the Russians, it's not going to have a strategic impact on the war itself," U.S. National Security Council spokesman John Kirby told reporters at the White House, "and it certainly isn't going to stop the Ukrainians or slow them down."