Jamaican sprinter Usain Bolt has claimed that he is preparing to be in his best form for the London Olympics next summer.

The 25-year-old, who is a multiple sprints world record holder, is currently training for the World Championships in Daegu but insists that his focus is elsewhere.

"I'm working my way up to the Olympic season, to being fit and ready then," The Mirror quotes Bolt as saying. "London is the key.

"I'm not in the tip-top shape I was in Berlin. Fitness wise I'm good, technique is almost there - but I don't think I'm in 9.5 shape."

Meanwhile, fellow countryman Asafa Powell has been forced to pull out of the World Championships due to injury.