Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty

Russian and Ukrainian officials offered conflicting views Thursday on the battle being waged over the eastern Ukraine city of Soledar.

Both sides described their forces as making progress in the fight for the salt mining town in the Donbas region.

"Our defenders continue to hold their positions on the most difficult frontlines and in the battle for (the) Donbas," said Hanna Maliar, the Ukrainian deputy of defense. "Today, fierce and heavy battles continue in the direction of Bakhmut, in the area of Soledar city."

Despite the "difficult situation," Ukrainian soldiers are desperately battling for control of Soledar, Maliar said.

"The enemy is suffering heavy losses, unsuccessfully trying to break through our defenses and capture Soledar," Maliar said. "Today, the city's approaches are literally littered with the bodies of Putin's destroyed troops. Nevertheless, they move over the bodies of their fallen fighters. Our defenders show maximum resilience and heroism."

But Kremlin spokesperson Dmitry Peskov said Thursday that Russian forces and mercenaries from the Wagner private military company are doing a "truly colossal job" in Soledar.

"These are absolutely selfless, heroic deeds," Peskov told journalists on Thursday.

Peskov said the hostilities in the region will continue.

"There is still a lot of work to be done. No time to stop, no time to rub our hands and so on. The main work is yet to come," Peskov said.

The Russian Defense Ministry said on Wednesday that Russia's airborne units had blocked Soledar from the north and the south and assault teams were fighting within the town limits.

Ukrainian President Volodymyr Zelenskyy said in his daily address on Wednesday that Ukrainian troops are holding onto Soledar.

"The terrorist state and its propagandists are trying to pretend" to have achieved some successes in Soledar, Zelenskyy said. "But the fighting continues."

Russia has replaced the military chief in charge in Ukraine, according to the Kremlin.

Army Gen. Valery Gerasimov, chief of the general staff of the Russian armed forces, will replace Sergei Surovikin, who has been commander of Russia's forces in Ukraine for the past three months. Surovikin will become one of Gerasimov's deputies, according to Sergei Shoigu, Russia's minister of defense, who made the new appointments.

The changes come as the progress of the Russian forces in Ukraine continues to stall.

"The increase in the level of leadership of the special operation is linked to the expansion of the scale of the tasks at hand and the need to organize closer interaction between troops," Shoigu said.

Ukrainian officials on Wednesday denied reports that the eastern Ukrainian city of Soledar is on the verge of being captured by Russian forces and claimed the battle for the city is ongoing.

The report contradicts British intelligence officials who on Tuesday said it appeared that Russian troops were close to capturing a salt mining town in an apparent attempt to cut off the enemy's supply routes. The British officials said Russian forces, along with mercenaries from the Wagner private military company, were likely in control of the city of Soledar, which is about six miles north of Bakhmut in the Donbas region, where heavy fighting has been reported in recent days.

The head of the Wagner group also released a statement on Telegram Tuesday, saying his mercenaries were in control of Soledar.

But Ukrainian officials said Wednesday the city has not fallen into the hands of Russian forces and the Russian mercenary group.

"Russians say that it is under their control; it is not true," said Serhiy Cherevatyi, a spokesperson for the Ukrainian eastern military command.

The Russian attack on Soledar is an apparent attempt to bypass Bakhmut from the north and disrupt Ukrainian supply routes, the British intelligence officials said. Part of the fighting is being waged near the entrances to the 124 miles of abandoned salt mine tunnels that run under the area.

On Tuesday, Ukrainian President Volodymyr Zelenskyy described the fighting in Soledar as "very difficult."

Senior Ukrainian officials said Tuesday that they believe any prospect of Russia launching a new offensive toward Kyiv from Belarus is "not likely at this moment."

The latest statement from Ukrainian officials contrasted with a series of interviews they gave last month in which they suggested Russia could mount an offensive early this year and even try to take Kyiv.

"Our assessment is that the Russians aren't in a position to make an advance on Kyiv from Belarus. And if that were their intention, it wouldn't happen for some time," a senior Ukrainian official said Tuesday.

The Ukrainian officials added that the mere threat of an assault from Belarus means that Ukrainian forces are "fixed" along the Ukraine-Belarus border.

-ABC News' Tom Soufi Burridge