Sir Mo Farah insists he has "done nothing wrong" in the wake of fresh allegations about his coach Alberto Salazar.

The four-time Olympic champion says he is frustrated and upset at having to defend himself against attempts to link him to "allegations of drug misuse".

Salazar, the head coach at the Nike Oregon Project in Portland, has again found himself at the centre of doping claims after a report from the United States Anti-Doping Agency (USADA), which was leaked to the Sunday Times, alleged he may have abused prescription medicines and drug infusions.

Farah has remained loyal to Salazar, who has denied all accusations of wrongdoing since doping allegations against him were first broadcast by BBC's Panorama programme in June 2015.

The Briton said in a statement: "It's deeply frustrating that I'm having to make an announcement on this subject.

"I am a clean athlete who has never broken the rules in regards to substances, methods or dosages and 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' 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."

The leaked report, the Sunday Times says, stated that Salazar gave six leading American runners intravenous drip infusions which "almost certainly" broke anti-doping rules.

The report, from March 2016, says athletes were given infusions of the chemical L-carnitine, a naturally-produced amino acid prescribed as a supplement for heart and muscle disorders. It is not a banned substance for athletes, but infusions of more than 50 millilitres in the space of six hours are prohibited.

The newspaper says that the USADA report contains allegations that Salazar gave athletes, including Farah, prescription drugs they had no medical need for to aid performance. For Farah, the Sunday Times says, this included potentially dangerous doses of permitted vitamin D medication to boost his testosterone levels.

The USADA document said that Farah's British doctors intervened over concerns for his health, the Sunday Times reports.

It also reportedly says Farah was given an infusion of L-carnitine shortly before his London marathon debut in 2014 from medical staff at UK Athletics (UKA), who were advised by Salazar and his staff. The volume of that infusion, the report says, is unknown.

UKA said a "small number" of British athletes had used L-carnitine "over the past few years", calling it a "legal and scientifically legitimate supplement" for endurance athletes.

It said that, as far as it was aware, "all doses administered and methods of administration have been fully in accordance with WADA approved protocol and guidelines".

A spokesman added in a statement that UKA had "fully cooperated" with the anti-doping authorities over the Salazar investigation and would continue to do so.

Salazar said athletes were given L-carnitine in "exactly the way USADA directed", the Sunday Times says.

USADA confirmed it had prepared a report "in response to a subpoena from a state medical licensing body regarding care given by a physician to athletes associated with the Nike Oregon Project", and that "a draft of this report was leaked to the Sunday Times by the Russian state-affiliated hacker group known as Fancy Bears".

Salazar refuted the allegations, saying in a statement quoted by BBC Sport: "The Times has simply recycled old allegations that have been refuted almost two years ago."

USADA launched an investigation into Salazar following the Panorama programme, but has not announced any evidence of wrongdoing.

Farah was questioned by its lawyers as part of that investigation, although he himself has never been under investigation.

The Briton has won four Olympic and five world titles over 5,000 and 10,000 metres since relocating to the United States to link up with Salazar in 2011.

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