Russian prime minister, Vladimir Putin, was greeted with whistles and boos on live television as he congratulated Russian heavyweight champion Fedor Emelianenko after beating American Jeff Monson.

He climbed into the ring at Moscow's Olympiisky Stadium on Sunday evening, but his attempts to give a speech were neutralised by boos and whistles from a 20,000-strong crowd.

Observers claim this is the first time Putin had been publicly booed. Russian television edited the footage to remove the booing, but viewers uploaded the television footage on YouTube, where it had gone viral, reaching 500,000 hits as of Monday morning. The news about Putin getting booed was the top news in the rating by the country's major online search engine Yandex as of Monday morning, according to the news website Ria Novosti.

Blogger Alexei Navalny posted the video on his site and wrote that it was "the end of an era" for the Russian leader, a judo black belt and a fan of martial arts.

Pro-Kremlin supporters denied the booing was directed to Putin and claimed instead that the crowd was "anxious" to get to the toilets

According to Ria Novosti, Putin had seen his approval rating falling significantly in recent months. Only 35 per cent support the premier, down from 61 per cent last February, according to a poll carried out by the independent Levada Center last month.

Emelianenko competes in the brutal Russian sport called mixed martial arts, which allows blows with legs and hands. It is also known in the country, somewhat appropriately, as "fight without rules."

Monson finished the match limping and covered in blood after a blow to his face. The sport, a mixture of boxing, wrestling and kick boxing, is known in the West largely as ultimate fighting or no-holds-barred fighting.