Listeners to the BBC's Today programme were taken by surprise this morning after comedian Jo Brand appeared to criticise one of the Radio 4 show's presenters.

As part of a pre-arranged joke, a serious-sounding Brand, who was introduced as a stand-in continuity announcer for Comic Relief, accused Sarah Montague of being a shoplifter and said that the presenter didn't have to wear a red nose, "because you drink so much".

The comedian also accused Montague of having misrepresented her in a previous interview, while the presenter herself made deadpan protestations of innocence.

A BBC spokeswoman said: "Today is Red Nose Day. Some continuity announcements are being taken over by comedians and it was clearly a joke."

Brand added: "I discussed it with Sarah beforehand, saying that I was going to muck around and she was fine with it."

Montague was in on the joke. In a podcast posted online after the show's completion, she said: "I was, I think, very dignified in response."

Later she added: "This was absolutely pre-arranged and I would happily have Jo as a continuity announcer any time."

Full transcript of Today programme interview

Jo Brand: "Yes hello Sarah, yes. Myself and other comics are doing continuity announcing yes. But enough of that. I've got a bit of a bone to pick with you Sarah... Last time I was on the Today programme, talking about charity, you sort of tried to imply that I didn't really care, I was just trying to advance my career, that I had a massive portfolio of shares, that I was a slum landlady. I feel like I want a formal apology from you."

Sarah Montague: "I'm sure I was just playing devils advocate and doing my job Jo."

Jo Brand: "I think you were playing devil Sarah. I mean does anyone mention your outstanding shoplifting charge? Or the fact that you don't actually have to wear a red nose because you drink so much? I mean it's not fair to imply that I'm the evil one in this partnership. Because I think you're the sort of person that Radio 4 needs to know about."

Sarah Montague [after a pause]: "Right Jo."

Jo Brand: "I'll see you later alright?

Sarah Montague: "I'll look forward to it"

Jo Brand: "Yeah, I'll be there. Don't worry."

Sarah Montague: "Do your job!"

Ed Stourton: "Nothing particularly humourous about the weather I'm afraid..."

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