The Chinese government has denied any involvement in bidding at an auction in Paris for two bronze artworks which it says were looted from Beijing in 1860.
A Chinese collector bought the heads of a rabbit and a rat for 15m euros ($19m; £13m) each, when fashion designer Yves Saint Laurent's collection was sold.
The buyer, Cai Mingchao, has refused to pay, as an "act of patriotism".
The official Xinhua news agency quoted an official as saying what Mr Cai had done was entirely a personal action.
"The State Administration of Cultural Heritage had nothing to do with it," said the head of the cultural bureau, Shan Jixiang.
He said his bureau did not know the identity of the bidder until Cai Mingchao, an adviser to China's National Treasures Fund that seeks to retrieve looted treasures, revealed himself.
Chinese bidder explains why he is not paying
The two bronzes were auctioned by Christie's in Paris last week as part of the estate of the late French fashion designer Yves Saint Laurent and his partner.
They were originally taken by British and French troops from the imperial Summer Palace in October 1860, towards the end of the Second Opium War.
China had tried to stop the sale, and later threatened the business of Christie's in China for having gone ahead.
But Christie's said the sale was legal, a position backed by a French court.
Mr Cai said his actions were to "stress that this money should not be paid".