Australians have been told not to travel to Hong Kong because of a dangerous rise in coronavirus cases.

The updated travel advice follows government warnings earlier this month warning Australians could be arrested and detained in Hong Kong, after China imposed sweeping national security laws.

Today's update to the Smart Traveller website now says: "Do not travel to Hong Kong".

People wearing face masks walk on a downtown street in Hong Kong

"There's been an increase in community transmission of COVID-19 in Hong Kong. Practise social distancing and wear a face mask in public spaces and on public transport."

Prime Minister Scott Morrison announced three weeks ago Australia was suspending its extradition agreement with the Chinese territory.

At the time, the Morrison government warned Australians living in Hong Kong they could be arbitrarily detained and transferred to China for prosecution, because of new laws.

Hong Kong authorities yesterday announced restrictions in response to a new community outbreak of COVID-19, but a full lockdown is not yet in place.

Restaurants will have to stop dine-in services, social gatherings are restricted to a maximum of two people instead of four, and mask wearing requirements have been extended.

Hong Kong has gone through a spike of coronavirus infections, with over 1000 new cases in the last two weeks.

More than half of Hong Kong's 2634 confirmed cases have been recorded in July alone.

Twenty people have died.

The tightened measures will be effective for at least one week starting tomorrow.

They are an extension of a previous ban on eating at restaurants after 6pm, as well as a mandatory wearing of masks on public transport.

The virus appeared to be under control in Hong Kong for months until July, when suddenly more and more cases of local infections started to appear.

With Associated Press

Source: 9News