Gordon Ramsay's most successful protégé has launched an extraordinary F-word attack on his former boss and says he wants to oust him as London's top superchef.

In his first major interview since an acrimonious split from Ramsay in May, Pétrus head chef Marcus Wareing says he would "lose no sleep" if they never met again.

He describes how working for the Scot made him feel "constrained, confined and trapped" and says he would rather "kill myself" than be overshadowed by the "sad bastard" who launched his career.

It is a bitter end to one of the most productive partnerships in recent London dining history with the pair boasting 15 Michelin star awards between them.

Lancastrian Wareing, 38, first met Ramsay, 41, at the start of their careers at Le Gavroche, and was hired to work at Ramsay's first solo restaurant project, Aubergine, in 1993.

There they worked "side by side, six days a week for two solid years".

Wareing became Ramsay's chief lieutenant, culminating in a deal for him to run the two-Michelin-starred Pétrus at the Berkeley Hotel as part of the Gordon Ramsay Holdings empire. They were such good friends that Ramsay was best man at Wareing's wedding.

Rumours the relationship had gone sour began to sweep round the restaurant scene last summer. The final break-up came in May, when the owners of the Berkeley Hotel said they wanted to work directly with Wareing when the current contract ends in September - a move that has been challenged by Ramsay's lawyers.

In the interview, published today in the August edition of Waitrose Food Illustrated, Wareing makes it clear their relationship is over for good.

He says: "If I never speak to that guy again in my life it wouldn't bother me one bit. Wouldn't give a f***. I admire Gordon, I learned a lot from him. But would I lose any sleep knowing he wouldn't be there? No chance."

Wareing explains why he wanted to remove himself from Ramsay's shadow: "Very simple. When you wake up in the morning and look in the mirror and all you see is a man who is constrained, confined and trapped, then you've got to change. My level of desire to expand has been reined in from time to time."

He admits that his "mentor" was the most important person in his life but says starting a family changed his perspective: "There was a time when my mentor was the person to keep happy. Now I've realised there's more to life than a mentor. I want to be my own man.

Wareing acknowledges "Gordon's an important part of my life" but he has a chilling warning for the man who has been the sole London holder of three Michelin stars for seven years.

He says: "Whatever happens between me and Gordon, if he wants me never to get to the status I want then my advice to him is: put a gun to my head, shoot me, put me in a box and bury me because if you don't, I'll come back and come back. I'll never give up until I get to where I want to go."

William Sitwell, editor of the magazine, said today Wareing's comments would "rock the food world and much beyond". He added: "You have to remember that Marcus Wareing has known Gordon since he was 19. They were best friends, Gordon was best man at his wedding. He's known him longer than anyone who's worked with him, even Gordon's family.

"He's never talked openly about Gordon, well not until now anyway..."

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