MO FARAH has responded to the revelation that he missed two drugs test in the build-up to the 2012 Olympics by categorically denying he has ever taken performance-enhancing drugs.

The British middle-distance runner has found himself increasingly under the spotlight following doping allegations made against his coach Alberto Salazar and training partner Galen Rupp, made initially in a BBC Panorama documentary.

Farah, who won gold in the 5000 and 10000 metres events in London, has released a statement via his Facebook page denying the rumours, while revealing the building speculation was taken its toll on his young family and pregnant wife.

The statement read: "I have never taken performance enhancing drugs in my life and I never will. Over the course of my career I have taken hundreds of drugs tests and every single one has been negative. I've fully explained the only two tests in my career that I have ever missed, which the authorities understood, and there was never any suggestion that these were anything more than simple mistakes.

"The last two weeks have been the toughest of my life - with rumours and speculation about me that are completely false - and the impact this has had on my family and friends has left me angry, frustrated and upset. In particular, the media pressure on my young family and my wife, who is 5 months pregnant, is extremely painful, especially as I'm away training for some important races.

"As I made clear, I went to Portland to speak to Alberto Salazar and demand answers. He reassured me that the claims are false and that he will soon be providing evidence to make that clear. Until then I will not be commenting further on the allegations.

"I would like to take this opportunity to thank my fans, family, friends and teammates for all the great support they have provided over the last few days and hope that I will now be allowed to focus on my training and winning medals for my country."