"The only thing I would say is that he is entitled to be competing," the former London 2012 chairman said, when asked about Gatlin's inclusion on the IAAF list during Securing Sport 2014 conference, organised by the International Centre for Sport Security here. 

"I'm not particularly comfortable about it.

"I think you'd be pretty surprised if I did sit here and was sanguine about that.

"I personally have big problems with that."

International Association of Athletics Federations World Athlete of the Year award nominee Justin Gatlin has twice been banned from competition after failings drugs tests
©Getty Images



Gatlin was first banned from international competition for two years after testing positive for amphetamines in 2001.

But he appealed on the grounds that the positive test had been due to medication that he had been taking since his childhood, when he was diagnosed with attention deficit disorder.

The appeal resulted in an early reinstatement by the IAAF and he returned to win the Olympic 100 metres gold medal at Athens 2004.

But Gatlin served a second ban, this time for four years, after testing positive for testosterone in 2006.