GENEVA - The Association of Summer Olympic International Federations said on Friday that a United States investigation into the World Anti-Doping Agency's approach to the case involving Chinese swimmers threatened to undermine the fundamental principles of the World Anti-Doping Code.

WADA held an online extraordinary executive meeting on Tuesday to discuss the interim report delivered by independent prosecutor Eric Cottier, regarding his review of WADA's handling of the Chinese Anti-Doping Agency's decision not to punish 23 Chinese swimmers who tested positive for the heart medication trimetazidine seven months before the delayed Tokyo Olympics in 2021.

CHINADA determined that the athletes had unintentionally ingested the substance, and WADA did not subsequently appeal CHINADA's decision, leading to criticism from athletes and the United States Anti-Doping Agency, who suggested a cover-up had taken place.

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"This federal investigation and the related issuance of a subpoena to World Aquatics' Executive Director regarding the anti-doping case involving Chinese swimmers threaten to undermine the fundamental principles of the World Anti-Doping Agency and the World Anti-Doping Code that applies universally," ASOIF said in its statement.

ASOIF expressed concerns that the leadership of one of its member international federations had been ordered to testify as a witness in a United States federal investigation.

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"Independent prosecutor Eric Cottier's interim report stated that WADA's actions showed no bias towards China and that WADA's decision not to appeal the contamination scenario presented by the China Anti-Doping Agency was 'indisputably reasonable'," ASOIF said.

ASOIF claimed the US criminal investigation into an anti-doping case on foreign soil threatened to undermine the role and independence of WADA.

"The US' extraterritorial investigation raises doubts about the personal safety of athletes, sport officials and representatives of international sport organizations and the confidence with which they may travel to the US for international sporting competitions and commitments," ASOIF added.

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The US will host the Los Angeles 2028 Olympic Games and many major international sporting competitions in the future, and ASOIF called on IFs to consider the risks of allocating future international events to the US.

ASOIF also urged the US Olympic and Paralympic Committee and the Los Angeles 2028 organizing committee to regard the position of WADA as an institution and respect the fundamental principles of the World Anti-Doping Code.

The International Olympic Committee also said that "the report clarifies that there were no irregularities on the part of WADA in handling the case" on Thursday.