Carol Thatcher faces being banned from the BBC after she referred to a tennis player as a "golliwog".

Thatcher, the daughter of former prime minister Lady Thatcher, made the remark in a private conversation in the green room of The One Show after the broadcast of the BBC1 programme on Thursday night.

Sources have said that Thatcher will not be used again on the show, where she is a roving reporter, until she formally apologises to those who were offended by the remark.

According to insiders, Thatcher – who won ITV1 reality series I'm a Celebrity, Get Me Out of Here! in 2005 – was chatting with The One Show host Adrian Chiles and guest Jo Brand about the Australian Open when she described an unnamed player as a "golliwog".

Show insiders said Chiles was "outraged" by the comment and he and Brand challenged Thatcher about it.

The pair also complained to show executives – as did production staff who later heard about the incident – and it is understood that Thatcher was approached the following day by the show's executive producer.

Thatcher's spokeswoman had not responded to a request for comment before publication, but was quoted in The Times today as saying the word was an "off-the-cuff remark made in jest" and that she had apologised to the show's producer.

Sources said Thatcher had also written to the show's executive producer to apologise and that the BBC was currently considering its decision.

However, insiders said this may not be enough.

"Her apology seems to be that it was just a joke, but the BBC feels it is not acceptable under any circumstances to call someone a golliwog," the source said.

"Unless you don't think that is an acceptable joke, how can you be sorry? Until she apologises to the people who were offended her future is in question. There are people working on the show who don't feel they can work with her. Adrian was outraged by what he heard."

A BBC spokesman said there were "no confirmed plans to work with Carol on The One Show at the present time".

He added: "The BBC considers any language of a racist nature wholly unacceptable. We have raised the issue with the individual concerned and are discussing it as a matter of urgency."

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