The Australian government has issued a travel advisory warning its citizens to stay away from Hong Kong.
On Thursday a "do not travel" alert was placed on the Australian Smart Travel website. It warns that new national security legislation "could be interpreted broadly".
"Under the new law you could be deported or face possible transfer to mainland China for prosecution under mainland law."
The advisory follows a sweeping new legislation which makes criticising China's government illegal.
On Wednesday China opened a new national security office in Hong Kong to oversee the enforcement of the new law.
The law is wide-ranging and makes inciting hatred of China's central government and Hong Kong's regional government illegal.
A wide range of crimes, including damaging public transport, could be considered terrorism, and those accused could face Chinese courts which have a near 100 percent conviction rate.
The travel advisory warns the new laws are vague.
"You may be at increased risk of detention on vaguely defined national security grounds. You could break the law without intending to."
As well as warning people not to travel to Hong Kong it also warns Australians living in the region to reconsider staying there.
Reuters reports Australian Prime Minister Scott Morrison will announce measures to assist Hong Kong citizens, including visas and changes to an extradition agreement.
Morrison has previously signaled Australia may follow Britain in offering visas to Hong Kong citizens after China imposed its new security law on the city.
The pending announcement comes after Australia's Foreign Minister Marise Payne held a teleconference with her counterparts in the Five Eyes security arrangement, which includes the US, about Hong Kong overnight.
New Zealand's Ministry of Foreign Affairs and Trade (MFAT) currently advises New Zealanders not to travel overseas at all due to the COVID-19 pandemic.
MFAT's latest travel advisory says the new security legislation can be "interpreted broadly".
"[It could lead] to increased risk of arrest and prosecution on national security grounds for a wide range of activity, including protest activity," reads the advisory.
"The maximum penalty under this law in Hong Kong is life imprisonment."
MFAT encourages all New Zealand citizens living in or travelling through Hong Kong to register with SafeTravel to receive up-to-date information.