Pair pose for pictures outside his London home
The couple have been linked since last November, but have kept their romance under wraps until now.
Yesterday, Sir Paul, 66, and Nancy, 47, who have just returned from a road trip across the States, posed for paps outside his St John’s Wood home.
The socialite locked arms with her lover as they walked to a nearby cafe.
Sir Paul is said to have cut short the romantic trip when daughter Mary, 38, gave birth to her first child with Simon Aboud, 43.
The photographer already has two sons Arthur, 8, and Elliot, 5, with ex-husband Alistair Donald.
‘It’s a very personal thing meeting a new grandchild for the first time, but he loves Nancy so much that he wanted her to be there,’ a source tells the Daily Mirror.
Macca’s divorce from second wife Heather Mills, 41, was finalised earlier this year.