Macquarie Group has cautioned against investing in Hong Kong companies which are exposed to the political winds of mainland China, following an official warning that the city's administrative "autonomy" is a privilege that can be removed at any time.

Hong Kong has retained its status as the financial hub of Asia since its handover from Great Britain in 1997, when Chinese leaders committed to retain a system of "one country two systems" for 50 years.

While Hong Kong enjoys 'one country, two systems' status, nothing, it seems, is set in stone. Credit:John Schauble

The city is home to more than 80,000 Australians while 550 Australian businesses have a "major presence" there, according to the Department of Foreign Affairs and Trade, but many are growing uneasy at the growing reach of Beijing.

On Tuesday, however, China's State Council released an unprecedented White Paper that said Hong Kong is just "one of the local administrative regions" and warns against "outside forces" using the city to interfere in China's domestic affairs.