Bronze animal heads that were looted from China's imperial Summer Palace in 1860

Chinese artist Zhao Bandi on Wednesday slammed last month's controversial sale at a Paris auction of two bronze animal heads looted from China's imperial Summer Palace in 1860.

"Businessmen are taking advantage of Chinese feelings of nationalism to make a thing so expensive," the conceptual artist, in Paris for a performance at a major museum, told AFP.

The bronzes, part of the art collection of late French fashion designer Yves Saint Laurent and his partner Pierre Berge, sold for 15.7 million euros (19.8 million dollars) each at an auction conducted by Christie's last month.

"They are not worth buying at this price," said Zhao, often known as the "panda-man" for his use of pandas in his art.

Authorities in Beijing had repeatedly called for the sale not to go ahead, and urged the relics be returned to China.

A Chinese art collector has said he was the bidder but has refused to pay the money, leaving the auction in limbo.