Heart surgery has put the kibosh on the remainder of Robin Williams's comedy tour Weapons of Self-Destruction.

Though now best known for his film roles, Williams, 57, returned to his stand-up comedy roots and embarked on a sold-out, 80-city tour in September. However, he postponed a handful of shows in Florida earlier this week, citing shortness of breath.

On Thursday, the actor-comedian revealed in a statement that he requires an aortic valve replacement and that his remaining tour dates must be cancelled.

"I'm so touched by everyone's support and well wishes," Williams said in the statement. "This tour has been amazing fun and I can't wait to get back out on the road after a little tune-up."

No details were revealed about Williams's current whereabouts, nor whether he has already been admitted to hospital.

Organizers expect to reschedule the cancelled dates or ticket-holders can obtain refunds at point of purchase.

Williams rose to fame on the 1970s television series Mork and Mindy, eventually moving on to a prolific film career with credits ranging from drama (Dead Poets Society, Awakenings, Good Morning Vietnam) to comedy and family fare (Hook, Jumanji, Aladdin, License to Wed).

He won an Oscar for his performance in the 1997 film Good Will Hunting.

With files from the Associated Press