Usain Bolt will not compete at next month's London Grand Prix at Crystal Palace because of Britain's tax laws.
That would put pay to organisers' hopes of setting up a three-way clash between Bolt and his chief 100metre rivals Asafa Powell and Tyson Gay.
"I am definitely not going to run," Bolt told a news conference ahead of Friday's Diamond League meeting in Paris.
Ricky Simms, the world 100 and 200m record holder's agent, confirmed to Press Association Sport that the reason was "the tax situation".
Bolt could lose money by competing at the Diamond League meeting which takes place on August 13 and 14 as British tax law stipulates that foreign sports stars have to pay taxes on their worldwide endorsements.
Bolt will go head to head with fellow Jamaican Powell at Friday's Diamond League meeting in Paris.
The 23-year-old equalled Powell's fastest time of the year by clocking 9.82 seconds last week in Lausanne on his return to competition following an Achilles' tendon injury.