Olympic champion Usain Bolt has claimed that he is "clean" following the news that fellow sprinters Asafa Powell and Tyson Gay have failed drugs tests.

Gay tested positive in an out-of-competition test in May, while Powell used a banned stimulant while at the Jamaican Championships last month.

"There's a lot of things that haven't been said so I'm just waiting to see what happens," Bolt said in a press conference. "In life things happen and people make mistakes.

"In life you learn anything is possible, but as an athlete you have to be aware, but that's why you have a team to have to help you out with these things.

"I was made to inspire people and run and that's the gift I have. I know I am clean and I just want to improve the sport and that is what I am going to do."

Bolt was speaking ahead of the Anniversary Games in London this week.