International auction house Christie's on Tuesday expressed hopes for greater openness in China's growing art markets before its first auction on the country's mainland.

"We're happy to operate here without the freedom to sell cultural relics, and when that changes we'll change with it," Christie's International chief executive Steven Murphy told a press conference.

He was referring to current rules barring foreign auction firms from selling cultural relics dated earlier than 1949.

"We're patient and we're respectful," he added, two days before the firm's first auction in mainland China, to be held in the commercial capital Shanghai.

"We're hopeful that will open up at some point."

The firm said in April it became the first international auction house authorised to operate in mainland China without a local partner.

Christie's, which has long operated in Hong Kong, had been organising sales in China since 2005 by authorising a Chinese auction firm to use its international trademark, due to strict regulations on setting up a solely-foreign invested auction house.

"Being here in China, which is a vital part of the world, is essential," Murphy said.

Murphy's remarks came as Christie's unveiled a three-day exhibition of items, ranging from Asian contemporary art to Western masterworks and jewelry, ahead of an auction Thursday evening.

Highlights include a contemplative 1963 still-life by Giorgio Morandi, Homme Assis by Pablo Picasso in 1969, and Andy Warhol's Diamond Dust Shoes of 1980-1981.

China has one of the world's largest and fastest-growing markets for art, with the country's buyers now common at international auctions.

Among the auction house's goals in China are "to connect Shanghai and therefore mainland China into Christie's network" which includes New York, London, Paris and Milan, Murphy said.

A total 27.9 billion yuan ($4.6 billion) worth of cultural relics and artworks were sold last year in the domestic auction market, according to China's commerce ministry.

"China's art market will remain on a long-term growth trend, judging from the growth in the Chinese economy and its wealthy population," Cai Jinqing, managing director for Christie's China, told reporters.

The population of millionaires in US dollar terms had reached 1.05 million in China by the end of 2012, Hurun Research Institute said in August, adding art collection is among the top five investment choices of China's moneyed classes.

Christie's, one of numerous business interests of French billionaire Francois Pinault, was at the centre of controversy in 2009 when two bronze animal heads looted from Beijing's Old Summer Palace in 1860 were put up for auction in Paris.

The animal heads were then owned by Pierre Berge, the partner of late French fashion designer Yves Saint Laurent, until Pinault acquired the two bronzes and handed them back to China in June this year.