LONDON (Reuters) - World snooker champion Ronnie O'Sullivan issued a statement on Thursday to clarify his comments after former world number five Stephen Lee was found guilty of match-fixing this week.

Lee faces a lifetime ban from the sport and O'Sullivan tweeted that he believed many other players had been involved in throwing matches.

The five-times world champion was asked to explain his comments by World Snooker chief Barry Hearn.

"I would like to clarify the comments that I made on Twitter 17th September as they were an instant reaction to an issue which I feel strongly about, namely the integrity of my sport," O'Sullivan said.

"The news about Stephen Lee's match-fixing case was eye-opening to all players on the circuit, and sends out a clear message to any would-be cheats.

"I fully support this decision and commend the (sport's ruling body) WPBSA for taking positive action in this case."

O'Sullivan said his reference to players throwing matches related to rumors from many years ago when the tour was much smaller than it is now.

"If I were aware of match-fixing, I understand that it would be up to me to report any fears to the Association," O'Sullivan said.

"I have no intention of undermining the integrity of the sport that I love and enjoy participating in so much and firmly believe that my tweets were taken out of context."

(Reporting by Ed Osmond, editing by Alan Baldwin)