From Hong Kong's central bank to China's largest property developer, Asian investors have a lot riding on London's real estate market.

Britain's decision to leave the European Union, commonly referred to as Brexit, has clouded the outlook for property, prompting asset managers to freeze withdrawals from real estate funds as investors rushed to redeem their money.

Commercial property values could fall about 10 per cent over the next year, led by declines in oversupplied central London, BlackRock said after the vote.

Investors from Asia accounted for 12 per cent of the £10.7 billion (S$18.7 billion) of direct real estate investment in Britain in the first quarter, making them the largest international group, according to Jones Lang LaSalle.

The country has been among the top five global real estate investment destinations for decades, especially for buyers from Singapore, China and Hong Kong.

"It's a confidence crisis," said Mr Reid Mackay, managing director of EastGate Asia, a real estate brokerage and advisory firm. "It will very much affect transactions that are pending."

Deals that are pending "are virtually put on hold. The transactions volume will probably fall", he said.

Still, some developers see Brexit as an opportunity. Chinese billionaire Guo Guangchang, chairman of conglomerate Fosun Group, said his company is increasingly eyeing development opportunities in Europe and particularly in Britain amid the current volatility.

City Developments, Singapore's second-largest developer, is also looking for bargains in the London property market and is ready to pounce in a fire sale, chairman Kwek Leng Beng has said.

Shares of Dalian Wanda Commercial Properties, which is building homes in London's Nine Elms district, have fallen 7.2 per cent in Hong Kong since June 23, the day Britain voted for Brexit.

China's largest developer China Vanke, whose shares started trading in Shenzhen on July 4 after being halted for more than six months, plunged almost 20 per cent this week amid a tussle for control with shareholders.

Yesterday, Barclays cut UK property markets homebuilder ratings to hold from buy, and London investor Great Portland Estates warned about weakening office markets in London.

The FTSE 350 Real Estate Investment Trust has fallen 19 per cent since the vote and the Bloomberg UK Homebuilder Index has slumped 35 per cent.

"In the near term, we expect confidence to reduce and some business investment decisions to be deferred whilst negotiations to establish our trading arrangements with the EU are undertaken," Great Portland said.

"As a result, we can expect London's commercial property markets to weaken during this period of uncertainty."

BLOOMBERG