Russian President Vladimir Putin on Monday complained of deteriorating ties with Western countries, which crumbled after he launched a full-scale offensive against Ukraine last year, as he accepted the credentials of several new ambassadors. 

At a Kremlin ceremony, Putin swore in some two dozen new ambassadors, including from countries such as Britain and Germany, with whom relations have been especially tense during the 21-month long offensive.

"The times are not easy," Putin told the envoys, with Russia hit by unprecedented rounds of Western sanctions as Moscow's offensive grinds on for another winter.

Addressing the new ambassador of the UK, with whom ties have been especially frosty even before the Ukraine offensive, he said Moscow and London were able to overcome differences in the 20th century.

"In the post-war (WWII) period and until recently, our countries were able to build relations," the Russian leader said.

"But the current state of things… is well known and we should hope that the situation — in the interest of our countries and nations — will change for the better."

Putin told the German ambassador that he regretted that Berlin was weaning itself off Russian energy.

"For over half a century we were able with Germany to develop a pragmatic business approach that was comfortable for both our countries and the whole European continent," said Putin, who speaks German and who was posted to Dresden during his time with the KGB.

"Our country without fail supplied Germany with ecologically clean gas," he said.

"This partnership was literally blown up by the explosion of the gas pipe," he added, referring to Nord Stream gas pipeline under the Baltic Sea that was damaged by a series of mysterious blasts in September 2022.

Putin told the new Swedish envoy that there was a "complete lack of communication" with Stockholm, which is readying to join NATO. 

Putin also regretted bad ties with Western ally South Korea. 

"As is well known, relations of Russia and Korea are unfortunately going through not the best period," he said, adding that he was "ready" to improve them. 

Putin angered Seoul by welcoming North Korean leader Kim Jong Un to Russia in September. He has also accepted an invitation to visit Pyongyang.