Sir Mo Farah has insisted he is "a clean athlete" following a newspaper report alleging the athlete's American coach Alberto Salazar may have broken anti-doping rules.
A leaked US Anti-Doping Agency (Usada) report, dated March 2016, and obtained by the Sunday Times alleges Mr Salazar routinely gave athletes legal prescription drugs without a justifiable medical reason.
The Sunday Times article reports Mr Salazar maintains that any drug use has always fully complied with the Wada [World Anti-doping Agency] code and athletes were administered with L-carnitine in “exactly the way Usada directed”.
Speaking on behalf of the doctor who administered the infusion of the legal supplement L-carnitine, UK Athletics told the Sunday Times: “To our knowledge, all doses administered and methods of administration have been fully in accordance with Wada approved protocol and guidelines.”
In response to the allegations against his coach, Sir Mo released a statement on Twitter and Facebook reaffirming he has "never broken any rules".
The Somali-born Briton said he "had done nothing wrong".
He said: "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."
Back in 2015, an independent audit into Sir Mo and his training programme, the Oregon Project, backed findings there was "no evidence of any impropriety" from the runner.
UK Athletics commissioned the audit into after it was alleged Mr Salazar and his US team, the Nike Oregon Project, had violated anti-doping rules and doped US record holder Galen Rupp.
The body found no evidence of wrongdoing by Farah in the initial findings of its investigation into allegations of doping against Mr Salazar, who strenuously denied all the accusations against him.