China to co-operate with doping probe into swimmers

China has indicated it will cooperate with an independent investigation into the events that led to 23 Chinese swimmers avoiding sanctions after testing positive for a banned substance months before the Tokyo Olympics.

Under mounting pressure over its handling of the initial case, the World Anti-Doping Agency (WADA) had said on Thursday it would launch an independent review led by Swiss prosecutor Eric Cottier.

WADA said it would also send a compliance audit team to China to assess the nation's anti-doping programme and invite independent auditors to join the mission.

"CHINADA will actively cooperate with the coming audit by WADA, and provide assistance where needed," said the China Anti-Doping Agency (CHINADA) in a statement on Friday.

"We noted that WADA has invited an independent prosecutor from Switzerland to review its handling of the no-fault contamination case involving 23 swimmers from China, which is a clear demonstration of fairness, openness and transparency of WADA."

Calls for an independent investigation had grown since the New York Times reported 23 Chinese swimmers tested positive for trimetazidine (TMZ), a medication that increases blood flow to the heart and is used to treat angina.

Swimming Australia had been among those governing bodies welcoming the review, saying it hoped the investigation would restore faith in global anti-doping systems ahead of the Olympic Games.

The swimmers were cleared by a Chinese investigation which said they were inadvertently exposed to the drug through contamination. The report determined the swimmers were staying at a hotel where traces of TMZ were discovered in the kitchen.

WADA has vigorously defended its handling of the case, saying it had no evidence to challenge China's findings and that external counsel had advised against appealing them.

"In the whole investigation process, CHINADA kept WADA and the Federation Internationale de Natation (FINA now known as World Aquatics) informed of relevant progress, and submitted the evidence from investigation, decisions made by CHINADA and the full case files," said CHINADA.

"Conclusions from the investigation and the decision were accepted by both WADA and FINA."

WADA's explanation of events has not kept a lid on growing outrage led by the United States Anti-Doping Agency (USADA), which has accused the global anti-doping body of a "potential cover-up" while dismissing the investigation and audit as toothless.

CHINADA fired back at critics, labelling the accusations as defamatory and misleading.

"These organisations and media have held misconceptions, made misjudgement and released inappropriate reports and announcements," said CHINADA. "The information they have published Is clearly contrary to the basic facts."