Sir Paul McCartney has revealed that he became a vegetarian after a fishing trip.

The 65-year-old, who appears in an ad campaign for Peta posing next to the words "I Am Paul McCartney, And I Am A Vegetarian" , said his views changed on the trip as he was "reeling in the poor fish".

"Something inside me clicked," he said. "I realised as I watched him fight for breath that his life was as important to him as mine is to me."

Sir Paul claims that if the world rejected meat there would be no more famine and he was once quoted as saying: "If anyone wants to save the planet, all they have to do is just stop eating meat.

"That's the single most important thing you could do. It's staggering when you think about it. Vegetarianism takes care of so many things in one shot: ecology, famine, cruelty."

Pamela Anderson, Forest Whitaker, Casey Affleck and Alicia Silverstone also star in the campaign.

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