The Russian offensive in eastern and southern Ukraine is not going according to Kremlin leader Vladimir Putin's plans, lagging two weeks or more behind his expectations. This was the opinion of the U.S. Department of Defense.

This was discussed at a briefing by a Pentagon spokesman.

According to the U.S. defense department, 99 Russian battalion-tactical groups (BTG) are involved in Ukraine.

"We assess that he (Putin) continues to build up forces in the Donbas... He continues to take casualties, he continues to see some of his capabilities diminish as they go into combat," said a senior Pentagon official.

He noted that there continues to be mostly artillery fighting on the fronts.

"And he, Mr. Putin, has not achieved any of the major objectives that we believe he wanted to achieve in the Donbass or in the south," the DOD official said.

In particular, battles continue in Mariupol. And although 10 BTGs have been moved north, the equivalent of 2 BTGs remain in the besieged city, while airstrikes continue on the Azovstal plant, where Ukrainian defenders are located.

"So he hasn't achieved the success that we believe he wanted to achieve, and certainly not in time. I mean, we can now estimate that he's two weeks or maybe even more behind what we thought or where he thought he wanted to be in the Donbas and in the south," the Pentagon spokesman said.

Earlier it was reported that the Ukrainian military in the Donbas repelled 15 enemy attacks in 24 hours, and fighting continues for Voyevodka, Toshkivka, and Nizhnee.