NEW YORK • Whistle-blower Vitaly Stepanov says he nearly aborted his plan to expose widespread doping in Russian athletics when the World Anti-Doping Agency (Wada) was slow to act on information he provided.

Stepanov, who previously worked for Russia's anti-doping agency, said he second-guessed himself countless times during a three-year stretch where information he fed to Wada did not lead to action.

"I was falling asleep and telling myself I am an idiot," he told Reuters. "That was probably my thought a lot of times. Especially after each major competition that was my thought. What am I doing?"

Stepanov, who had more than 200 e-mail exchanges with Wada starting in 2010, provided evidence for a German television documentary called Top Secret Doping: How Russia Makes Its Winners that led to the establishment of a Wada independent commission last year.

"I was frustrated with myself," said Stepanov, who is now living in an undisclosed location in the United States with his wife.

"That was half of the time. The other half of the time there was hope Wada was looking for ways to deal with this issue and you have to be really patient.

"I thought the best I could do was provide the information and hope it was used for the right reason."

Wada's spokesman Ben Nichols told Reuters the agency acted as soon as it could. Before last year, Wada did not have the authority to conduct its own investigations under the World Anti-Doping Code, according to Nichols.

But Travis Tygart, chief executive of the United States Anti-Doping Agency, when asked about the Wada inaction, said: "From a clean athlete prospective, it is really hard to stomach that they didn't. It rattles confidence in the system."

Based on the Wada commission report, the International Association of Athletics Federations (IAAF) suspended Russian athletics from international competition, including the Aug 5-21 Rio Olympics.

The IAAF Council will decide on June 17 whether to reinstate Russia and to allow Stepanov's wife Yuliya, who served a two-year doping ban, to compete in Rio.

Russia's sports ministry said that a full probe has been carried out and a "road map" agreed with Wada to reform the anti-doping process.

"These efforts thus ensure the independence and transparency of doping control in Russia, which is fully supported by the state," the ministry said in a statement.

It also said it was "certain" about the transparency of its doping controls during the 2014 Winter Olympics in Sochi, Russia, and that independent observers had managed the testing operation daily.

Stepanov told CBS News in an interview aired on Sunday that the former head of Russia's drug testing laboratory, Grigory Rodchenkov, had informed him that he had evidence of a testing cover-up and at least four Russian gold medallists in 2014 were using banned steroids.

REUTERS