(Bloomberg) -- Russia and Ukraine reported widespread fighting along the war’s front lines as anticipation mounts for a long-planned Kyiv’s counteroffensive.

The Defense Ministry in Moscow said its forces defeated a large-scale Ukrainian attack in the south of Donetsk region on Sunday involving tanks and mechanized battalions. “The enemy did not achieve its objectives, it had no success,” the ministry said in a statement early Monday. 

Ukraine’s deputy defense minister, Hanna Malyar, said Russian officials are spreading disinformation to distract from their losses around city of Bakhmut, which is in the northeast of Donetsk region and has been the focus of heavy fighting for months. 

“The area around Bakhmut remains the epicenter of fighting,” Malyar said, adding that Ukrainian troops advanced to the north and to the south of the city as they try to encircle the occupying forces. “We are having success there.” Neither account could be independently verified. 

The General Staff in Kyiv reported “combat engagements” during the past day including fierce fighting near the Donetsk region town of Maryinka. Ukrainian troops repelled all Russian attacks and “the enemy continues to concentrate its main efforts on attempts to fully occupy Luhansk and Donetsk regions,” it said on Facebook.

Russian military bloggers highlighted Ukrainian advances amid fighting around the village of Novodonetske, southwest of the city of Donetsk, although, again, those accounts couldn’t be confirmed. 

The war that’s now in its 16th month is entering a potentially decisive phase as Ukraine masses forces for its push to reclaim Russian-occupied regions of the country’s south and east, backed by billions in weapons supplied by Kyiv’s US and European allies. 

Ukraine Recap: Top Aide Questions Readiness for Counteroffensive

Meanwhile, Russia continued its campaign of air strikes against Ukraine, firing six cruise missiles and eight Shahed drones, the General Staff in Kyiv said. Air defenses downed four missiles and six drones, it said.

Russia’s Defense Ministry said naval tactical groups began “operational exercises” in the Baltic Sea on Monday through June 15. Some 40 warships, naval vessels and support boats are involved as well as more than 3,500 personnel and 25 aircraft and helicopters, it said on Telegram. 

--With assistance from Daryna Krasnolutska.

(Updates with report of Ukrainian advances in fourth paragraph)

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