After three top anti-doping advisers to FINA resigned in protest at their advice on Russian cases being ignored ahead of the Rio Olympics, the world swimming body has expressed surprise at their walkout.
FINA responded in a statement on Sunday that it "obviously regrets" the resignations by Doping Control Review Board chairman Andrew Pipe of Canada, and two others from the eight-member panel.
Though FINA had barred seven Russian swimmers for past positive tests or links to state-backed doping, they were allowed to compete in Rio.
Responsibility for those decisions ultimately lay with the IOC and Court of Arbitration for Sport, FINA said.
"Concerning the claims expressed in their resignation letter, FINA would like to clarify that the Olympic Games are an IOC event," swimming's governing body said.
Pipe's resignation letter reportedly criticised FINA over its handling of the process.
"We were disappointed to note that our recommendations were not followed - and even more disappointed to receive no specific response to a subsequent written request for information regarding the reasons for FINA's decision," Pipe wrote, according to PA.
FINA insisted on its integrity in a letter of response by president Julio Maglione to the former officials.
"FINA always coordinates with all stakeholders in the sport movement to assure that transparency and zero tolerance in the fight against doping is in place, thus protecting the clean athletes," Maglione wrote.
That claim appeared to clash with concern expressed by United States swimming and anti-doping officials in the months leading up to the Olympics about the rigour of FINA's work to combat drug cheats.
A doping case involving China's star swimmer Sun Yang, a two-time 2012 Olympic freestyle gold medallist, was shrouded in mystery in 2014.
His positive test for a banned stimulant and subsequent three-month ban was confirmed in China and by FINA only after it was served.
FINA has also resisted suggestions to retest samples taken at the 2015 world championships hosted by Russia, held months before the first of two World Anti-Doping Agency inquiry reports detailed the country's state doping program.
