Sir Paul McCartney will marry for the third time after proposing to his girlfriend of nearly four years, it has been announced.

His publicist Stuart Bell confirmed that the former Beatles singer had got engaged to New York socialite Nancy Shevell.

Mr Bell refused to give any further details, saying only: "We're all thrilled for him."

Sir Paul, 68, who has a home at Peasmarsh, near Rye, and Ms Shevell started seeing each other in Long Island's Hamptons area in late 2007.

The singer-songwriter's first wife, Linda, died of cancer in 1998 and he divorced his second wife, Heather Mills, in 2008.

Ms Shevell, 51, who sits on the board of New York's Metropolitan Transportation Authority, is said to get on well with Sir Paul's children.