London, Oct 30 : The World Anti-Doping Agency and the International Tennis Federation have criticised tennis golden boy Andre Agassi for his admission that he took drugs, but the eight-time Grand Slam champion is likely to avoid retrospective punishment.

Agassi's image has suffered after he made a sensational confession that he lied to tennis authorities about his use of hard drugs in order to escape a ban.

Agassi tested positive for the highly addictive drug, Crystal Methamphetamine in 1997 and duped the Association of Tennis Professionals into believing he had taken it by accident.

WADA, founded in 1999, cannot take any action against Agassi because of the agency's eight-year statute of limitations, The Mirror reports.

"He obviously hasn't been able to sleep and he's come out and made a confession. You have to applaud that to a degree. But we're stuck by our eight year limitation rule, so we can't do anything," said WADA director general David Howman.

Under Tennis rules at the time, Agassi's actions might have warranted a three-month ban but WADA's current guidelines now provide for a sanction of up to two years if an athlete cannot prove mitigating circumstances.

WADA president John Fahey added: "We would expect the ATP, which administered its own anti-doping programme at that time, to shed light on this allegation."

On Thursday, the International Tennis Federation expressed its "surprise and disappointment" over the revelations made by Agassi.

"We would hope Andre Agassi might now see his way to be a role model and alert the youth and Tennis players to the dangers of drug use," ITF president Francesco Ricci Bitti said.

The American tennis legend revealed his use of the substance in his new autobiography "Open" and that he received a call from a doctor working for the ATP in the autumn of 1997 to inform him that he had failed a drug test. (ANI)