Whistle-blower Grigory Rodchenkov has warned that allowing Russian athletes to parade with their national flag at the closing ceremony of the Winter Olympics on February 25 would be "the worst decision."
In an interview broadcast on February 24, Rodchenkov told the BBC that the International Olympic Committee (IOC) faces "the most important moment in its history" when it decides whether Russia's delegation can march under the Russian flag at the ceremony in Pyeongchang, South Korea.
Russia was banned from the games over what the IOC described as a state-run, systemic doping program at the Winter Olympics in Sochi in 2014, but 168 Russians were allowed to compete under the Olympic Athletes from Russia (OAR) designation and the Olympic flag.
The IOC executive board has delayed a decision on whether to lift the suspension for the closing ceremony until February 25.
Rodchenkov, the former director of Russia's anti-doping laboratory, organized the Russian system of doping before fleeing to the United States in 2016 and providing evidence of it to investigators.
Russian officials have repeatedly denied state involvement in doping.
The BBC said it travelled to a secret location in the United States to interview Rodchenkov, who is under U.S. protection.
The 59-year-old "insisted on wearing a face mask to conceal his new identity because of a perceived security threat from Russian agents," it also said.
Speaking about the IOC's upcoming decision, Rodchenkov said the organization "should show how they are consistent with the fight against doping."
"Russian officials reject any charges, they say I am a liar, they humiliated all whistle-blowers, they gave false information in court, and if the flag will be allowed to appear it will be the worst decision.
Rodchenkov said that "the Olympics could die" if anti-doping reforms are not made.
He accused the IOC of "falsifying the fight against doping," which he said is also being "sabotaged" by international sporting federations.
"In general many countries and many national anti-doping organizations are not interested at all to catch leading athletes in their countries," he said.
Rodchenkov also reiterated his claim that he was just part of a doping system that went to the very top of Russia's state, including President Vladimir Putin and Vitaly Mutko, who was the minister of sport from 2008 to 2016 and is now deputy prime minister.
"I absolutely followed orders. It was teamwork. FSB [Russia's Federal Security Service] was involved when we had to control coordination," he said.
"[Mutko] knew absolutely everything, and he reported to the president," he added. "I know he reported to Putin, he told me that."
Putin has repeatedly denied Rodchenkov's claims, and accused him of forging evidence against Russian athletes at the behest of unspecified "foreign" forces. Russian authorities have not provided evidence of such allegations.
Last month, the Russian president called Rodchenkov a "jerk" who should not be trusted.
'Ready For Everything'
Mutko has denied allegations of wrongdoing and is currently appealing a lifetime ban from the IOC.
Asked where he would be if he had not left Russia, Rodchenkov replied "in a tomb" or a psychiatric clinic.
"It will be torture. It's no way to go back to Russia, it's a big, big danger and threat to my life," the whistle-blower said.
The Russian Investigative Committee has filed charges against Rodchenkov in Moscow, alleging that he abused his powers when he was Russia's anti-doping director. He was ordered arrested in absentia.
Rodchenkov is also facing a legal challenge at the New York State Supreme Court, where three former Russian biathletes filed a $30 million libel lawsuit against him.
"I'm ready for everything," he told the BBC. "In regards to all these charges I know many things which remain undisclosed and were they to continue this, they will deeply regret their decision to sue me.
With reporting by the BBC