Picasso portrait of his lover sells for double its estimate at £25m

A painting by Pablo Picasso of his secret teenage lover has sold for £25.2million at auction.

La Lecture - which shows the artist's 17-year-old mistress Marie-Thérèse Walter snoozing in an armchair - went for double the estimate at a Sotheby's sale in London last night.

The picture is one of a series of erotic paintings of the teenager Picasso painted in the early Thirties. Bond Street dealers were nervous before the auction about the bubbling paint surface on Picasso's panel, while several disliked its pale and unerotic colouring.

One or two declared the estimate to be "risky". Afterwards all were confident £25million was right. "Quite correct," said Mayfair dealer Helly Nahmad who dropped out at £16million.

"Absolutely right for a mini-trophy picture," said James Roundell of Dickinson Roundell in St James's. Sotheby's defended its cautious estimate, pointing out that La Lecture had failed to sell for £3 million in 1996. Expert Charles Moffatt said: "This is a fine example of a conservative estimate yielding a very solid price. Aggressive estimates drive down price, low estimates allow the saleroom time to think and bid."

The Impressionist and Modern auction produced a total of £68million - including a record £2.2million for a work by René Magritte - with 84 per cent sold. Sotheby's chairman Henry Wyndham said: "It points to another buoyant year on the art market."

The £25 million price of the Picasso has an impact on the value of the world's most expensive painting, La Rêve (The Dream), the biggest of the Marie-Thérèse series. It was priced at £92 million by owner Steve Wynn of Las Vegas in 2007. Dealers now estimate it at well over £100 million.