A FAMOUS sketch from BBC Scotland cult comedy favourite Chewin' The Fat has been deleted from repeats due to a derogatory racial slur.

The clip featuring the character "Auld Betty", a lewd pensioner played by Karen Dunbar, is among several removed by censors after being deemed unsuitable for modern audiences.

The revelation is made by comedian and actor Dunbar in a new documentary that explores the changing world of acceptable humour, outdated language and the thorny truth about "cancel" culture.

"What came up was a derogatory term for Japanese people," she says. "As soon as I saw it, I was like, 'Oh, my God …"

The one-hour programme #CancelKarenDunbar is due to air on BBC Scotland on Thursday. Dunbar admits: "I don't know how to do comedy without offence. I don't know how to actually speak without offence now."

READ MORE: Karen Dunbar: 'I'm terrified of being cancelled over old comedy gags'

In a cover story interview with The Herald Magazine today, Dunbar also discusses the "discomfort" she felt viewing another controversial clip from the BBC archives: a jarring scene from the sitcom Fawlty Towers.

The episode, which first aired in 1975, shows the character Major Gowen repeatedly using the N-word in reference to members of the West Indies cricket team, while also referring to Indians as "w***".

When this segment airs in the #CancelKarenDunbar documentary, it will do so unbleeped and accompanied by a viewer discretion warning.

The Herald:

In the magazine interview, Dunbar describes the strong reaction she had watching the scene. "It is well beyond discomfort that I felt," she says. "To see that clip for the first time, my stomach lurched."

She also reveals which infamous Chewin' The Fat sketch – dubbed "a national treasure" – has managed to avoid ending up in the comedy sin bin.

To read the full interview with Karen Dunbar in The Herald Magazine, click here