Russia reportedly lost more ground in Ukraine on Wednesday while failing to make any "significant advances" in its ongoing offensive in the country, according to a U.S. think tank.

The Institute for the Study of War (ISD), which focuses on research and analysis regarding defense and foreign affairs, and provides daily updates on the war in Ukraine, said in its May 11 assessment that Ukrainian forces took further ground northeast of Kharkiv.

"The Ukrainian counteroffensive north of Kharkiv City has forced Russian troops onto the defensive and necessitated reinforcement and replenishment efforts intended to prevent further Ukrainian advances towards the Russian border," the ISD said.

"Russian efforts along the Southern Axis and in Donetsk and Luhansk Oblasts remain similarly stalled, and Russian forces have not made any significant gain

The Russian offensive in Ukraine is currently concentrated in the eastern Donbas region, but recent reports from the ISD indicate that Russian President Vladimir Putin's troops have faced several consecutive days of either ground losses or little to no progress in gaining ground.

An ISD map with terrain control assessments shows that Russia still holds a stretch of land in the east of Ukraine as of May 11, particularly in the self-declared pro-Russia separatist states, but the Ukrainian counteroffensive is chipping away at some areas along the edge of the Russian-held territory.

Newsweek reached out to Russia's Defense Ministry seeking confirmation of the May 11 ISD report. The Twitter account for the Russian Defense Ministry has not posted a briefing on the war since April 26, and Newsweek was not immediately able to access the ministry's website to view any potential updates that were issued more recently.