Picasso painting of lover fetches £40.7m at auction

A Picasso portrait of his teenage mistress sold for £25,241,250 in a sale of Impressionist and modern art at Sotheby's in London last night.

The painting of Marie-Thérèse Walter, La Lecture had not been displayed in public for 70 years. It had been expected to fetch £18m.

Marie-Thérèse was only 17 years old when, stepping off the Paris Metro one day in 1927, she was approached by a stranger and told: "I am Picasso! You and I are going to do great things together!"

Their relationship remained secret for many years because of her age and the fact that the artist was married, but she was the subject of several of his most celebrated pictures.

For the next four years the Parisian girl appeared in several of his works, but only in coded form.

La Lecture shows Ms Walter asleep in a chair, and was the first full painting the artist exhibited.

The painting was bought by an anonymous telephone bidder. It was painted in 1923 and shows Ms Walter asleep in a chair.

After it was exhibited in Paris in 1932 it passed through several private collections before being offered for sale by an American collector. It was contested by six bidders.