Turning vegetarian is the biggest change anyone could make in their lifestyle to help the environment, Sir Paul McCartney said today.

The former Beatle said the world's meat industry was one of the major contributors to global warming, as he urged people to "turn veggie'' to tackle the problem.

"I would urge everyone to think about taking this simple step to help our precious environment and save it for the children of the future,'' he said.

Sir Paul, who turned vegetarian many years ago after watching lambs play in a field outside his home, made the comments in an interview with US animal rights organisation Peta.

Asked what was the most personal change a person could make to help the environment, he said: "I think the biggest change anyone could make in their own lifestyle would be to become vegetarian.

"The surprising thing is that even though many of us, including me, were brought up as traditional meat and fish eaters, it is a simple matter these days, and an exciting one, to consider changing your diet to a healthier one which not only brings benefits to the person who does it but also to the planet as a whole.'' He said he found it "very surprising'' that most major environmental organisations left vegetarianism off their lists of top ways to tackle global warming.

"Of course there are many powerful businesses which would wish to resist this idea but it is becoming clearer that a simple change in people's lifestyles could make a major difference to our environment,'' he said.

"What is interesting is that nowadays it is so easy to become vegetarian and so many people are reducing meat in their diet.

"That is a simple but extremely effective step that many people could take to help the environment and improve their own health at the same time.'' In the same interview, Sir Paul, 65, who went through a high-profile £24.3m divorce settlement with Heather Mills last month, said "thoughtless industrialisation'' was destroying the planet.

"This scandal can be halted and there are hopeful signs that people are starting to realise that this must be done to secure a brighter future for our children and theirs,'' he said.

Sir Paul is the latest celebrity to appear in a Peta advertising campaign promoting vegetarianism.

Along with stars including Alicia Silverstone, Casey Affleck, and Forest Whitaker, the former Beatle dons an "Eat no animal'' T-shirt for the campaign.

A Peta spokesman said a recent UN report concluded that raising animals for food generates more greenhouse gas emissions than all the cars, trucks, ships, and planes in the world combined. Researchers at the University of Chicago also found that switching to a vegan diet was more effective at countering global warming than switching from a standard American car to a hybrid Toyota Prius