HONG KONG (Bloomberg) - Billionaire Paul Allen plans to part with a trophy from his prized art collection. A vibrant abstract painting by Willem de Kooning, Untitled XII, will be among the top highlights of Art Basel Hong Kong, an international fair that opens next week. It is priced at US$35 million (S$46 million).

Asian billionaires have been snapping up Western masterpieces at an accelerating pace. China is the second largest market for art after the US.

Collectors from South Korea and China have purchased at least 10 major de Kooning paintings in the past decade, according to Mr Brett Gorvy, a former chairman of Christie's postwar and contemporary art.

Billionaire collectors like Mr Allen, a co-founder of Microsoft, often prune their art holdings to finance new purchases.

"This sale is part of normal course of business for a collector like Paul," said Ms Alexa Rudin, a spokesman for Vulcan, Mr Allen's family office that manages his business and charitable interests and whose staff includes 15 art experts.

The de Kooning - a vortex of flesh-toned brushstrokes and irregular shapes accentuated with bubblegum pink and sky blue - was painted in 1975, the beginning of a two-year stretch considered among the most accomplished in the Abstract Expressionist artist's life.

The artist was in his 70s and newly in love with a much younger woman. "I made those paintings, one after another, no trouble at all," he would later recall, comparing himself to a man at a gambling table who "feels that he can't lose", according to an exhibition catalogue.

Mr Allen bought the de Kooning privately in 2001.