Chef Gordon Ramsay (AFP photo)

Celebrity chef Gordon Ramsay turned down a bizarre request from a fan who offered to donate $9,540 to charity if the star hurled abuse at him.

The Hell's Kitchen host, who is known for his acid tongue and scathing put-downs, was approached by the devotee who offered to hand the money to a good cause if he spoke to him rudely as a gift for his birthday, according to Britain's Daily Express newspaper.

Ramsay says, "I was in Vegas and this guy came up to me and said: 'It is my 50th birthday. Would you mind calling me a donkey?' I said: 'I'm not calling you a donkey.' Then the guy said: 'I will donate £6,000 to charity,' but no I didn't do it."