Irish sailor Peter O'Leary has been let off with a warning after betting on a direct competitor to win at the 2008 Beijing Games, the International Olympic Committee (IOC) have revealed.

O'Leary placed two bets worth a total of €300 the British boat to capture the gold medal in the Star class at odds of 12-1, and won €3,600.

"There was no proof of any match-fixing," IOC spokesman Mark Adams told reporters. "The athlete was unaware he could not bet on Olympic events.

"It is not something we agree with and we condemn it but we will not take any more action."

The IOC bars athletes from betting on Olympic events but the organisation's ethics commission said competitors in 2008 may not have been as familiar with the regulations as they are now.

O'Leary failed to qualify for the medal race on which he had bet.

The affair, which broke just before he competed at the London Games earlier this year, made headlines and prompted an IOC investigation.

The IOC has been eager to tackle gambling and corruption by monitoring betting patterns during the Games and informing athletes of what they can and cannot do.

O'Leary and team mate David Burrows finished 10th in the Star competition in London.