The document obtained by The Sunday Times alleges the American head coach of the controversial Nike Oregon Project gave Sir Mo and other athletes potentially harmful legal prescription drugs when they had no medical need.

Dated March 2016, the report was passed to the British newspaper by Russian hacking group Fancy Bears.

In a statement released, 58-year-old Salazar denied the claims by USADA and maintained his stance against doping in sport.

"I believe in a clean sport," said the three-time winner of the New York City Marathon. 

"I do not use supplements that are banned.

"I have clearly and repeatedly refuted allegations directed against me and the Oregon Project.

"The Oregon Project will never permit doping and all Oregon Project athletes are required to comply with the World Anti-Doping Agency (WADA) Code and International Association of Athletics Federations (IAAF) rules."

The report also claimed that Salazar used a banned method of infusing a supplement called L-carnitine, the effects of which he reportedly boasted about to Lance Armstrong, stripped of his seven Tour de France titles after he admitted doping. 

Although L-carnitine is not a banned substance, infusions of more than 50 millilitres within a six-hour time frame are prohibited.

According to The Sunday Times, the document states USADA has "substantial and compelling" evidence that Salazar and Houston endocrinologist Jeffrey Brown "conspired to collude together" to use prescription medications to boost performance.

Brown’s lawyers have denied the charges and said the use of L-carnitine was approved by USADA.

The Sunday Times story does not state whether any of the report’s stated conclusions are out of date.

Responding to these claims, Salazar said any use of L-carnitine is done "within WADA guidelines".

"In this case, to ensure my interpretation of WADA rules was correct, I also communicated in writing with USADA in advance of the use and administration of L-carnitine with Oregon Project athletes," he said.

"I have voluntarily cooperated with USADA for years and met with them more than a year ago.

"The leaking of information and the litigation of false allegations in the press is disturbing, desperate and a denial of due process.

"I look forward to this unfair and protracted process reaching the conclusion I know to be true."

Sir Mo, winner of the 5,000 and 10,000 Olympic metres gold medals at both London 2012 and Rio 2016, said in a statement on his Facebook page that he has "never broken the rules in regards to substances, methods or dosages".

He added: "It is upsetting that some parts of the media, despite the clear facts, continue to try to associate me with allegations of drug misuse.

"I'm unclear as to The Sunday Times's motivations towards me but I do understand that using my name and profile makes the story more interesting, but it's entirely unfair to make assertions when it is clear from their own statements that I have done nothing wrong.

"As I've said many times before, we all should do everything we can to have a clean sport and it is entirely right that anyone who breaks the rules should be punished.

"However, this should be done through proper process and if USADA or any other anti-doping body has evidence of wrongdoing, they should publish it and take action rather than allow the media to be judge and jury."

Salazar has been under investigation since a BBC Panorama programme in 2015 made allegations about drugs use at his United States training base.

It was claimed that London 2012 Olympic 10,000m silver medallist Galen Rupp was given the banned anabolic steroid testosterone in 2002, when he was 16-years-old.

In June 2015, Salazar released a 12,000-word open letter providing a detailed rebuttal of the allegations that Rupp has ever taken a banned substance.

Rupp has also denied the claims.