"This is an ex-dog. It has ceased to be"

It doesn't quite have the same ring to it, but John Cleese has revealed that Monty Python's most quoted sketch was very nearly written about a canine.

The revelation about the origins of the famous Parrot Sketch, co-written with Graham Chapman in 1969, comes in the second half of Victoria Wood's Sketch Show Story, to be shown on BBC1 on November 1

In the same show, the Two Ronnies reveal how their classic 'Four Candles' sketch was inspired by a letter from an ironmonger in Hayes, Middlesex.

Other comics talking about the real people who spawned comedy characters will include Harry Enfield, Lenny Henry and French and Saunders.