British Prime Minister Boris Johnson said Wednesday said he would offer millions of Hong Kong residents a path to British citizenship if China imposes a national security law that opponents fear will erode political freedom in the territory.
"Many people in Hong Kong fear their way of life - which China pledged to uphold - is under threat," Johnson wrote in op-eds published in the South China Morning Post and the Times of London.
China's parliament approved a proposal last week allowing mainland security and intelligence agents to be stationed in Hong Kong for the first time, which analysts say could facilitate an ability to suppress opposition.
The proposal was approved in response to recent waves of pro-democracy protests in Hong Kong.
"If China proceeds to justify their fears, then Britain could not in good conscience shrug our shoulders and walk away; instead we will honor our obligations and provide an alternative," Johnson wrote.
Johnson reiterated Britain's vow to grant British National Overseas passport-holders in Hong Kong a possible route to citizenship, allowing them to settle in the United Kingdom.
Johnson estimated there are about 350,000 holders of BNO passports in Hong Kong and another 2.5 million who are eligible for them.
The BNO passport is basically a travel document that lacks citizenship rights. Britain issued them to Hong Kong residents before it handed it over to China in 1997 after more than 150 years of colonization.
Hong Kong residents were supposedly guaranteed a high level of autonomy and political freedom when Britain handed over the city.
The prime minister's promise comes as several countries, including Australia, Canada and the U.S., are facing international pressure to make residential accommodations for Hong Kong residents seeking refuge from repression in the former British colony.
Hong Kong democracy activist Joshua Wong requested that Britain go beyond offering Hong Kongers a path to British citizenship.
"I call upon the UK government to impose necessary sanctions and restrictive measures," Wong said.
Chinese Foreign Ministry spokesman Zhao Lijian defended China's approval of the proposal, maintaining national security issues are internal matters and that Britain's association with Hong Kong stemmed from "aggressive colonization and unequal treaties."
"The UK's irresponsible remarks and accusations ...have grossly interfered in China's internal affairs including Hong Kong affairs," Zhao said. "We advise the UK side to step back from the brink."