Oscar winner Dame Helen Mirren was left red-faced after a foul-mouthed slip of the tongue on BBC Breakfast.
The star was discussing her role in the re-make of Arthur and John Gielgud's part in the original when presenter Sian Williams remarked that he was famous for swearing a lot.
Dame Helen replied: "Well, in that sort of wonderful voice he had... You little s**t."
She immediately realised her mistake and covered her mouth before saying: "I'm so sorry."
It is not the first time the actress has been caught out live on air.
In 2007, she swore on camera during a red carpet interview at the Baftas.
The film, which also stars Russell Brand, has its UK premiere in London tonight.