The World Anti Doping Agency (WADA) has challenged the exoneration of Pakistani fast bowlers Shoaib Akhtar [Images] and Mohammad Asif [Images] from doping charges in the Court of Arbitration for Sports, in Lausanne, Switzerland [Images].

WADA media relations manager Fridiric Donzi said the Agency on Thursday filed the appeal exercising its right as given in the WADA code.

"WADA has exercised its independent right to appeal, provided in the World Anti-Doping Code, to the Court of Arbitration for Sport against the Pakistani Cricket Board's appeal panel decision to overturn the sports sanctions of two athletes who recently tested positive for performance enhancing drugs," Donze said.

"As WADA believes that the decision to overturn the sports sanctions is not in conformity with the World Anti-Doping Code, WADA has exercised its responsibility to ensure proper implementation of and compliance with the Code," he said.

The WADA appeal comes after the International Cricket Council also announced few days back it would support any such move by the Agency.

Shoaib and Asif were banned for two and one year respectively by a PCB appointed drug tribunal after the duo tested positive for steroid nandrolone in out-of-competition dope tests conducted by the Board ahead of the Champions Trophy in India.

But an appeals committee lifted their bans, saying the pacemen did not take the banned drug 'intentionally'.

Donze said WADA had determined that it had the right and the duty to appeal in the circumstances in the interest of doping-free sport and the uniform application of the Code in all sports and for the protection of athletes who were not doping.

Sources said the dissenting report on the exoneration of the two bowlers by one of the members of the appeal's panel, Dr Danish Zaheer, would be used by WADA in the CAS to strengthen their case.

Pakistan is preparing for a hard tour of South Africa with Shoaib and Asif called up for a training camp for the selection of the final touring squad.

The WADA appeal could also jeopardise their appearance in the World Cup in the West Indies [Images] as there is every likelihood that the CAS might direct the two players to undergo fresh tests under WADA supervision.