Rage Against The Machine would not do what the BBC told them to today - by swearing during a live performance of their song Killing In The Name on Radio 5 live.
The band, who are poised to beat X Factor winner Joe McElderry to this year's Christmas number one, were featured on the station's breakfast show.
Frontman Zack de la Rocha, was heard letting rip with expletives four times towards the close of the song, during the anthemic chant: "F*** you I won't do what you tell me."
Presenter Shelagh Fogarty was heard saying "Get rid of it," as the song was abruptly faded out.
She added: "Sorry. We needed to get rid of that because that suddenly turned in to something we were not expecting."
She added jokingly: "So buy Joe's records."
A BBC spokesman said: "5 Live breakfast featured a live broadcast of the song Killing In The Name by Rage Against The Machine.
"We had spoken to the band repeatedly beforehand and they had agreed not to swear.
"When they did we faded the band out and said sorry immediately. We apologise again to anyone who was offended."
An internet campaign has been running to push the anti-establishment 1990s hit to the top of the charts, in protest at the dominance of X Factor singles during recent Christmases.