Speaking to BBC Radio Five Live's Nicky Campbell, he described himself as a "pacifist" who had concerns about the way the war had been conducted.

"I felt that the UN all agreed that Saddam should be made to disarm. They didn't agree on how to do it," he said.

Along with wife Heather Mills, Sir Paul is a vigorous anti-landmine campaigner and has expressed his disgust at the use of cluster bombs during the fighting.

"It would be great to outlaw these cowardly weapons," he said.

"What happens after the war finishes is that it's the civilians - mainly women and children - who get blown up.

"A lot of people agree that there are other ways to do it. I don't want anyone to fight anyone," he added.

Jackson debate

The interview will be broadcast on Monday to coincide with the release of the War Child Hope album.

Featuring artists including Sir Paul, David Bowie and Cat Stevens - with his first pop song for 25 years - profits will go towards charities aiding children in Iraq.

Sir Paul, who is currently touring the UK, also waded in on the debate on US star Michael Jackson, calling him an "unusual guy".

"I feel sorry for the kids being brought up under those veils whereas I was keen to send my kids to ordinary school and just throw them into the lion's den," he said.