Mystery over sale of Klimt

Flower Garden, a masterpiece by the Austrian artist Gustav Klimt, is expected to fetch between pounds 3m and pounds 4m when it is sold at Christie's in London on 28 November, writes Geraldine Norman.

The painting, a blazing pyramid of colour treated in an almost mosaic technique, was once the proud possession of the Prague National Gallery and has been sent for sale by a Swiss private collector.

Klimt was Vienna's leading avant- garde painter at the turn of the century.

Flower Garden was painted on his summer holidays some time between 1905 and 1907, then exhibited at the breakaway Vienna Kunstschau of 1908. Two years later it was exhibited in Prague and snapped up by the National Gallery.

Mystery surrounds the way in which the National Gallery got rid of it in 1968. According to Christie's it was swapped for some other pictures; they don't know by whom or what it was exchanged for. The man who organised the swap sold it to the present owner.

'We have checked with the museum in Prague,' James Roundell, of Christie's, said.

'They told us about the exchange. It was perfectly above board.'

(Photograph omitted)