The painting, one of the artist's favourite subjects, has been in the same family since 1879 when it was bought from a gallery in Paris by a friend of Edgar Degas. Danseuse au repos shows a young dancer relaxing, and was unveiled at Sotheby's in London yesterday - the first time it had been seen anywhere outside Paris.
Michel Strauss, the co-chairman of Sotheby's Impressionist, Modern and Contemporary Art, said it was the most beautiful work by Degas to have appeared on the open market since 1983 when a painting called L'Attente fetched pounds 2.1m in New York.
Danseuse belonged to Jules-Emile Boivin, a French industrialist and co- founder of the Sommier sugar company.
Before its sale on 28 June at Sotheby's, London, the pastel, with others from the Boivin collection, will be exhibited in Paris, New York and Zurich. Another pastel by the artist, Femme assise devant un piano, which was also owned by the Boivin family, will be sold at the auction.
Both works belonged to a series by Degas featuring women in interiors, which Mr Boivin bought in the 1880s. His collection of six works has been split and one, Danseuses, is in the Musee D'Orsay after the family gave it to the French government in lieu of inheritance tax.Reuse content