A Picasso painting of his mistress which was saved from the Nazis has been sold by Christie’s in New York for $45 million (£35 million).

Femme assise, robe bleue (1939) was sold to his friend Paul Rosenberg , who kept it in his collection near Bordeaux.

He fled to the US in 1940 and the collection was found by the Nazis and stored in a Paris museum. When word got out to the Free French forces of plans to move crates of art out of Paris by train in 1944, Mr Rosenberg’s son Alexandre was among a group sent to capture the train The daring raid was immortalised in the 1964 movie The Train, starring Burt Lancaster and Jeanne Moreau.