Olympics chief Thomas Bach called for a complete overhaul of the global anti-doping system on Tuesday after revelations of State-backed cheating by Russia rocked preparations for the Rio Games.
Mr. Bach said the uncovering of widespread Russian doping had shown up deficiencies in the World Anti-Doping Agency (WADA).
"Recent developments have shown that we need a full review of the WADA anti-doping system," he told an International Olympic Committee (IOC) session, three days before the Rio Games open on Friday.
"The IOC is calling for a more robust and efficient anti-doping system," he said. "This requires clear responsibilities, more transparency, more independence and better worldwide harmonisation."
Mr. Bach's condemnation of WADA escalates a feud between the Olympics and anti-doping bodies, which broke out in the run-up to Rio.
WADA led calls for Russia to be kicked out of the Rio Olympics after it published a report which found the Sports Ministry and secret services duped drug testers by switching samples at laboratories.
But the IOC stopped short of a total Russian ban and instead delegated individual sports to take action against athletes from the country, drawing accusations it was passing the buck.
However, Mr. Bach blasted the prospect of an outright Russian ban in graphic terms. "Let us just for a moment consider the consequences of a 'nuclear option'.
"The result is death and devastation. This is not what the Olympic movement stands for."
He added: "We want to keep the cheaters away from the Olympic Games. There is no place to hide for cheats and dopers can never feel safe anywhere."
Several IOC members also criticised WADA during Tuesday's talks, before the body voted 84-1 to implement last month's executive board decision not to exclude Russia.
WADA president Craig Reedie largely took the comments in his stride but he insisted the anti-doping body wasn't in as bad a shape as some delegates had suggested.
"I heard a view this morning that the system is broken," Reedie told the IOC delegates.
"I would like to say that all of it is not broken, part of it is broken and we should start identifying those parts that need attention."
Russia's athletics team had been barred in a separate doping scandal, and at least 117 of Russia's original Olympic contingent of 387 have also been excluded over drugs concerns.
Many have taken their cases to the Court of Arbitration for Sport, including 17 rowers and the Russian weightlifting federation, with the country's eventual contingent still unclear.
Russian Olympic Committee President Alexander Zhukov blasted "discrimination" against athletes who have been banned as a result of the WADA report, despite not failing drugs tests.
"To those who crave collective disqualification for Russia, taking into account ruined fates and broke lives of innocent athletes, I fully agree with the position of president Bach that each individual must have at least the opportunity to prove their innocence," he said.
Argentina's Gerardo Werthein also hit out at WADA's "failure to investigate serious and credible allegations more swiftly" as IOC members rounded on the anti-doping body.
"It saddens me to say this, but at times WADA has seemed to be more interested in publicity and self-promotion rather than doing its job as a regulator," Werthein said.
Reedie later said he was "personally offended" by Werthein's comments and revealed that he confronted the Argentine during a break in the meeting.
"He assured me he wasn't speaking about me and he maybe overstated his case. We remain friends," said the Scot.