Australia has banded with the United Kingdom and Canada in describing China's plan to impose a strict national security law on Hong Kong as deeply concerning and undermining the city's autonomy.
Beijing wants to introduce the legislation that would expand its ability to monitor and oversee Hong Kong's security operations and target people seeking to undermine China's authority.
The proposal was raised at China's National Congress and follows the widespread protests by Hong Kong residents concerned Beijing was undermining the freedoms promised when the city was handed back to China by the UK in 1997.
Australia's Foreign Minister Marise Payne, British Foreign Secretary Dominic Raab and Canadian Foreign Minister Francois-Philippe Champagne have issued a statement critical of China's plan.
"The legally binding Joint Declaration, signed by China and the United Kingdom, sets out that Hong Kong will have a high degree of autonomy," the three ministers said.
"It also provides that rights and freedoms, including those of the person, of the press, of assembly, of association and others, will be ensured by law in Hong Kong and that the provisions of the two United Nations covenants on human rights … shall remain in force."
The trio suggested it could be a power grab.
"Making such a law on Hong Kong's behalf, without the direct participation of its people, legislature or judiciary, would clearly undermine the principle of 'One Country, Two Systems', under which Hong Kong is guaranteed a high degree of autonomy," the ministers said.
Pro-democracy camp accused of having CIA backing
Chinese officials say they may directly set up special offices in Hong Kong to oversee the city's national security efforts in the wake of last year's pro-democracy unrest.
A state-controlled news agency accused the city's pro-democracy opposition of having "schemed with external forces in attempts to create a 'colour revolution'".
Beijing has repeatedly alleged that the pro-democracy camp was receiving support from the CIA in the United States, as well as other foreign governments.
A Chinese official said the National Congress was exercising its "constitutional power" to set up a new legal framework and enforcement mechanism to ensure national security in Hong Kong.
Activists say the new laws could be a knockout blow for Hong Kong's one country, two systems deal with China.