Millions for Mao

A new record was set for Andy Warhol's work, when his 1972 portrait of China's Chairman Mao sold for $17.36m (£9.19m) at Christie's in New York. Two other portraits of classic Warhol subjects - Marilyn Monroe and Jackie Kennedy - sold for over $30m in total.

Willem de Kooning's Untitled XXV fetched $27.1m.

The $240m sale set new records for 19 artists and caps a fortnight in which Christie's and rivals Sotheby's took $1bn between them.

Mao was sold by the Zurich-based Daros collection and was bought by Hong Kong collector Joseph Lau.

Before the sale, more attention had been focused on Orange Marilyn, a 1962 picture, which took $16.2m, and Sixteen Jackies, which made $15.6m. Sixteen Jackies is a black and blue series of the wife of President John F Kennedy on the day of his assassination in 1963. As well as Untitled XXV, another de Kooning - Woman (Seated Woman I) - broke a record. At $9.6m, it became the most expensive of the artist's works on paper.

A work by abstract expressionist Clyfford Still, 1947-R-No 1, reached $21.2m, more than three times its estimate, and another new record.

Records were also set for works by Richard Diebenkorn, Louise Bourgeois, Arshile Gorky and Gerhard Richter.

"Tonight's sale caps an incredible two weeks at Christie's where we have seen record totals and unprecedented depth in the market in all fields," the auction house's chief executive, Edward Dolman, told news agency AFP.