Hong Kong has been wracked by more than two months of protests.

Beijing on Tuesday voiced "strong dissatisfaction" with a joint statement issued by the G7 leaders, who backed Hong Kong's autonomy and called for calm after months of civil unrest.

G7 leaders meeting in France on Monday backed Hong Kong's autonomy as laid out in a 1984 agreement between Britain and China, and called for calm in the protest-hit city.

But Beijing has accused foreign governments of interfering over Hong Kong, and foreign ministry spokesman Geng Shuang said the G7 was "meddling" and "harbouring evil intentions".

"We express our strong dissatisfaction and resolute opposition to the statement made by the leaders of the G7 Summit on Hong Kong affairs," Geng said at a press briefing in Beijing.

"We have repeatedly stressed that Hong Kong's affairs are purely China's internal affairs and that no foreign government, organisation or individual has the right to intervene."

Hong Kong has been wracked by more than two months of protests over an attempt by its Beijing-backed government to pass an extradition bill which opponents saw as a huge dent in the city's autonomy.

It has since morphed into a wider call for greater democratic freedoms.

In the G7 statement, the leaders of Britain, Canada, France, Germany, Italy, Japan and the United States called for calm.

Beijing has previously accused former colonial power Britain of interfering in the semi-autonomous Chinese territory, which was handed over to China in 1997.

"The rule of law, social order, economic livelihood and international image of Hong Kong has been severely affected," Geng said.

"No one cares more about the prosperity and stability of Hong Kong than the Chinese people, including the people of Hong Kong."

The financial hub faced more violence over the weekend, with police saying Monday that they were forced to fire water cannon and a warning shot to fend off "extremely violent" demonstrators, marking some of the worst violence in the last 12 weeks of political unrest in the city.

So far Beijing has not intervened over unrest in the semi-autonomous city, despite ramping up the rhetoric against demonstrators and mounting fears that they may act militarily to quell the violence.