A portrait by Austrian artist Gustav Klimt has sold for $4m (�2.75m).

The painting, Portrait of a Lady in Red from 1897-1898, fetched more than twice its expected price, suggesting a recovery in the art market after last month's uncertainty in the wake of the attacks on the US.

Helena Newman, the art expert in charge of the sale, said: "It is reassuring that prices for the best examples in the modern art field are as good as ever, and that strong bidding was coming from both sides of the Atlantic."

Art expert Emmanuel Di-Donna said: "This is the first sale of this importance since the attacks in New York - and everybody was awaiting to see how the market was going to react."

Erotic

The Klimt painting had not been seen in public before and had been in private hands since it was first acquired from the artist.

The collection of German and Austrian art was sold for just under �10m.

Kilmt, born in 1862, is seen as the founder of the school of painting known as the Vienna Secession, and one of the great exponents of Art Nouveau.

But the frequently disturbing and erotic themes of his work led to much criticism in his lifetime.

He died in 1918.