The advisory is likely to heighten tensions between the sides that have spiked since Beijing's imposition on Hong Kong of a strict new national security law in June that has already been met with a series of punitive US actions.

The statement warned US citizens that China imposes "arbitrary detention and exit bans" to compel co-operation with investigations, pressure family members to return to China from abroad, influence civil disputes and "gain bargaining leverage over foreign governments".

In Hong Kong, China "unilaterally and arbitrarily exercises police and security power", the advisory said, adding that new legislation also covered offences committed by non-Hong Kong residents or organisations outside Hong Kong, possibly subjecting US citizens who have publicly criticised China to a "heightened risk of arrest, detention, expulsion or prosecution".

Chinese foreign ministry spokesman Wang Wenbin told reporters at a daily briefing the US should "fully respect the facts and should not engage in unwarranted political manipulation" when issuing such advisories.

"China has always protected the safety and legal rights of foreigners in China in accordance with law. China is one of the safest countries in the world," Wang said. "Of course, foreigners in China also have an obligation to abide by Chinese laws."

Last month, the Trump administration suspended or terminated three bilateral agreements with Hong Kong covering extradition and tax exemptions, citing Beijing's violation of its pledge for Hong Kong to retain broad autonomy for 50 years after the former British colony's 1997 handover to Chinese rule.

Other Western nations have also suspended extradition treaties with Hong Kong following the national security's law's passage.

Australian Associated Press