Comedy legend John Cleese has said that he is retiring from writing and performing because he will never be able to write a better sitcom than Fawlty Towers.

Instead, the Monty Python star will write a book on the history of comedy and has revealed plans to become a "comedy professor", according to The Times.

He commented that too many young writers compose sitcoms aimed at US teenagers that ignore the "basic principles" of comedy.

Cleese said "It is very rare to see someone with that grasp of old-fashioned comedy."

He went on, saying "The last truly excellent performance I saw was Eddie Izzard. But Ricky Gervais is also a match for the great American sitcoms."