A sample given by Russian heavyweight boxer Alexander Povetkin has tested negative ©Getty Images

A sample given by Russian heavyweight boxer Alexander Povetkin has tested negative and “no doping has been detected”, his promoter Andrei Ryabinsky has claimed.

Povetkin failed drugs test for banned muscle booster ostarine in a test conducted by the Voluntary Anti-Doping Association (VADA), forcing the abandonment of his scheduled world title fight with Canadian Bermane Stiverne last Saturday (December 17).

The 2004 Olympic gold medallist had been due to take on Stiverne for the vacant World Boxing Council (WBC) heavyweight title.

But the WBC withdrew their recognition of the fight and launched an investigation after the failure, which was Povetkin’s second of the year after he tested positive for meldonoum in April.

Despite the doping claims, Povetkin was allowed to go up against France’s Johann Duhaupas in a non-title fight in Yekaterinburg, which sparked controversy in Russia and in worldwide boxing circles.

The 37-year-old Russian, a former World Boxing Association heavyweight champion, knocked out the Frenchman in the sixth round.

In what represents the latest installment to the ongoing saga surrounding Povetkin, Ryabinsky denied his boxer was cheating in a post on Twitter.

“We have just received the results of Povetkin’s new doping sample taken by the Voluntary Anti-Doping Association on December 13,” he said.

“He is clean, no doping has been detected.

“It is what they call honest American sport.

“We are probing into this case.”

The WBC decision was announced on Twitter by the body's President Mauricio Sulaiman.

Ostarine was added to the World Anti-Doping Agency (WADA) Prohibited List in 2008 as a designer steroid described as a selective androgen receptor modulators (SARM).

It is thought to be particularly beneficial building up muscle mass during training periods.

Povetkin remained defiant, claiming in an interview with Russia's official news agency TASS that hw “did not know how the substance got in to my body”.

“What sense does it make to use doping and fail the last test?” he said.

“It is all senseless.”

Povetkin escaped a WBC ban in April, despite failing for the banned heart attack drug meldonium.

The produce was banned by WADA on January 1, but they subsequently admitted that "more research" was required to assess how long traces of the substance could remain in the human body.

A scheduled fight against United States' Deontay Wilder was cancelled as a result of the first failure.