After being out in the cold, impressionist works are set to shoot to favour at major art auctions in London this week as buyers from Asia and Russia step in where Japanese collectors once feared to tread.

"Since the middle of last year, there's been a strong demand for Impressionist works, which had been squeezed out for three years prior due to the boom in contemporary art," said Samuel Valette, head of Impressionist and Modern Art at Sotheby's France.

The accent currently is on quality, he said, with a fold of new buyers from Asia and Russia, as well as European and US investors, "looking for the very best", he said.

That meant not only the aesthetic quality of a work but also its origin, he said.

Christie's has said it expects the London sale of 63 modern and impressionist artworks today to raise between €196 and €276 million.

Impressionist oils enjoyed a golden age on the art market in the late 1980s, when enthusiastic Japanese buyers sent prices soaring for the best as well as the not-quite-best works produced by the turn-of-the-19th-century school.

When investors from Japan dropped out of the market however after 1990, due to the economic squeeze, Impressionism took a dive, Mr Valette said.

"Nowadays the market is more balanced. The Japanese are still present but so are Russians, the rest of Asia, America and Europe.

For some new investors, "Impressionism is a first step in joining the art market", said Thomas Seydoux, Christie's international director of Impressonist and modern art.

First-time buyers appreciate the movement's "decorative side, the bright colours, the contrasting shade", he said.

In the last few years however the market has evolved, with collectors nowadays going for works from the post-1890s rather than earlier oils from 1870 to 1880.

"Tastes have changed in favour of works with more matter," said Seydoux, referring to the switch from oils depicting rural scenes to urban Impressionist works.

Among the top 15 works sold under the hammer for over 50 million dollars, Monet is in 8th position with a 1919 Water-Lily Pond that went for $80 million in 2008 in London.

Renoir's Au Moulin de la Galette is in ninth position after fetching $78.1 million in 1990 in New York.