A desk believed to have once been owned by the mistress of King Louis XV of France has sold for more than £3 million at auction, setting a record for a piece by the French furniture-maker who created it.

The desk was the highlight of an auction at Christie's in London, Masterpieces Formerly in The Collection of Monsieur and Madame Riahi. Djahanguir Riahi, a French-Iranian, amassed a world-class collection of 18th century furniture and works of art, and pieces from his collection made almost £20 million at the London sale.

The desk, an ormolu-mounted Japanese lacquer secretaire-a-abattant, dates from about 1755 and is thought to have been in the renowned collection of Madame de Pompadour, the royal mistress to King Louis XV of France. It was made by Bernard II van Risen Burgh, and its sale price - £3,177,250 - was a world record for a piece by the craftsman.