Supermodel Naomi Campbell has threatened to take legal action over a Cadbury advertisement that allegedly uses her name to promote a chocolate bar.

According to reports, the catwalk beauty accuses the chocolate giant of racism after an advertising campaign that not only uses her name without permission – but also “compares her to chocolate”.

The ad for Cadbury's Bliss shows a chocolate bar surrounded by diamonds with the slogan, "Move over Naomi, there's a new diva in town".

Campbell alleges the tag line is a jibe aimed at her and claims she is deeply offended at being compared to a chocolate bar.

"I am shocked. It's upsetting to be described as chocolate, not just for me, but for all black women and black people. I do not find any humour in this. It is insulting and hurtful," she told UK’s Independent.

"It's upsetting to be described as chocolate, not just for me, but for all black women and black people as a race. I do not find any humour in this. It is insulting and hurtful."

The supermodel's mother, Valerie Morris, is said to have echoed her daughter's concern, "I'm deeply upset by this racist advert. Do these people think they can insult black people and we just take it? This is the 21st century, not the 1950s. Shame on Cadbury".

A spokesperson for Cadbury said: "(The ad is) a light-hearted take on the social pretensions of Cadbury Dairy Milk Bliss ... we would never produce any type of marketing we felt might cause any offence to any section of society ... (The ad is) no longer in circulation ... we have no plans to repeat the campaign."