Sir Paul McCartney is reportedly making secret preparations to marry US heiress Nancy Shevell.

The Beatles legend is said to be keen to tie the knot for a third time with Nancy, his girlfriend of nearly two years, and organised a family meet up in the Caribbean earlier this month to discuss their future together with his children.

A friend of the 67-year-old musician told the Daily Express newspaper: "Paul and Nancy's relationship is rock solid and there's no mad hurry for a wedding.

"Next year has certainly been mentioned as the most likely time, but neither of them want some big deal made out of it.

"It's almost certainly going to be done very discreetly over in the US and Paul would ideally like to do it without any publicity beforehand, but whether he could pull that off is another matter."

Heather Mills - Paul's second wife and mother to his youngest daughter, six-year-old Beatrice - has been informed of his plans to tie the knot with 48-year-old Nancy, according to friends.

Charity campaigner Heather was married to 'Let It Be' singer Paul from 2002 to 2008, when they went through a bitter divorce, in which she secured a £24.3 million payout for her and Beatrice.

Paul's first marriage, to vegetarian frozen food pioneer Linda, was one of the most happy and successful in showbiz, lasting from 1968 until her death from cancer in 1997.

New York-based Nancy is a businesswoman of high standing, and holds the position of Vice President of Administration at her father's company, New England Motor Freight.