Henri Matisse bronze could fetch $35m
A life-size bronze sculpture by Henri Matisse could fetch up to $35m (£22m) when it goes up for auction next month.
The work, titled Back IV (Nu de Dos, 4eme etat), will be on offer at Christie's in New York on 3 November.
Owned by an anonymous private collector, it has never been sold at auction before.
Conor Jordan, head of impressionist and modern art at Christie's America, said it was a "milestone in the evolution of modernist style".
"Conceived on an epic scale, Back IV is a powerfully reductive expression of the human form," he added.
The sculpture is from a series of four that Jordan described as the artist's most ambitious project.
"We expect tremendous enthusiasm from collectors around the world who will recognise this superb bronze as one of the most important sculptural achievements of the 20th century," said Jordan.
There were 12 bronzes produced of each piece in the series.
Among the 12 Back IV works created, all but two are in museum collections including London's Tate Modern, the Pompidou Centre in Paris and the Museum of Modern Art in New York.
Earlier this year, Christie's sold the most expensive work ever auctioned, Pablo Picasso's Nude, Green Leaves and Bust, which made $106.5m (£70m).