"We believe that [China] could be a large market, simply because of the [mainland's] currency restriction," said Richard Mathieson, chairman and managing director of Cai-Capital.

Mathieson's agency is helping two Hong Kong buyers complete deals for London properties by using bitcoin.

Beijing is taking steps to discourage investment in bitcoin and reduce trading of the virtual currency by mainland banks.

Legal experts said that while bitcoin would enable mainlanders to bypass Beijing's foreign exchange curbs, the virtual currency was perceived by many as risky. Large fluctuations in value, the prospect of more regulations and the threat posed by hackers were just some of the downsides, they said.

Bitcoin is a kind of virtual payment method that works peer-to-peer without a central repository and no single administrator. It is also known as a crypto-currency or digital currency.

Cai-Capital director Keith Stukins said the company provided the means for customers who wanted to use bitcoins to buy overseas properties. The bitcoins would be converted through the Acquire CC Exchange, which is registered in the Channel Islands, he said. Developers would not receive bitcoin but would take the converted currency - in this case pounds.

According to the crypto-currency process, Cai-Capital creates a digital wallet, which is stored off line and is encrypted and password-protected.

Mathieson said one of his Hong Kong clients was buying a London home for £1 million (HK$13 million) and the other was picking up a flat for £750,000.

Mathieson, who has 20 years' experience in serving Hong Kong buyers of British properties, said the company planned to expand on the mainland, but no deal was under negotiation at this stage.

Simon Deane, partner and head of the finance and insolvency department at Deacons, who focuses on banking legislation and regulations, said that technically, using bitcoin to buy properties would bypass foreign exchange restrictions.

"However, the buyers need to find a vendor who is willing to accept payment in bitcoin first," Deane said.

He echoed the views on potential risks arising from further regulation, a lack of confidence in the virtual currency and hacking.

International property consultants were unfazed by Cai-Capital's move, citing the risks in the currency. International property consultants such as Jones Lang LaSalle, Knight Frank and Savills said they did not accept bitcoin.

Gavin Sung, head of International Residential Sales (Asia) at Savills, said: "I do not foresee this becoming a dominant trend … It is a nice PR exercise."