Sir Paul McCartney has branded his marriage to Heather Mills one of the worst mistakes of his life.

The Beatles legend wed the former glamour model in 2002, but the couple separated in 2006, leading to an ugly public divorce battle.

The union was officially dissolved in 2008 and the veteran musician was forced to hand over $38.9 million of his fortune, as well as annual payments for the former couple's young daughter, Beatrice.

In a new interview with Britain's Q magazine, McCartney was asked if getting married again was his greatest error of the last decade and he replied: "OK, yeah. I suppose that has to be the prime contender."

He adds, "These things happen. I tend to look at the positive side, which is that I have another beautiful daughter out of it."