A new visa scheme offering millions of Hong Kongers a pathway to British citizenship will go live later on Sunday as the city's former colonial master opens its doors to those wanting to escape China's crackdown on dissent.
From Sunday afternoon, anyone with a British National (Overseas) passport and their dependants will be able to apply online for a visa allowing them to live and work in the United Kingdom. After five years they can then apply for citizenship.
The immigration scheme is a response to Beijing's decision last year to impose a sweeping national security law on Hong Kong to snuff out huge and often violent democracy protests.
Britain has accused China of tearing up its promise ahead of Hong Kong's 1997 handover that the financial hub would maintain key liberties and autonomy for 50 years. London argued it has a moral duty to protect its former colonial subjects.
"We have honoured our profound ties of history and friendship with the people of Hong Kong, and we have stood up for freedom and autonomy," Prime Minister Boris Johnson said of the scheme this week.
China has reacted with fury to the visa offer.
On Friday it announced BN(O) passports would no longer be recognised as a legitimate travel or ID document.
The move was largely symbolic as Hong Kongers tend to use their own passports or ID cards to leave the city.
But Beijing said it was prepared to take "further measures", raising fears authorities might try to stop Hong Kongers from leaving for Britain.
It is not clear how many Hong Kongers will take up the offer, especially as the coronavirus restricts global flights and mires much of the world, including Britain, in a painful economic malaise.
But a BN(O) passport is available to a huge number of people -- about 70 percent of Hong Kong's 7.5 million population.
Applications for BN(O) passports have skyrocketed more than 300 percent since the national security law was imposed last July, with 733,000 registered holders as of mid-January.
Britain predicts up to 154,000 Hong Kongers could arrive over the next year and as many as 322,000 over five years, bringing an estimated "net benefit" of up to £2.9 billion ($4 billion).
The BN(O) passport is a legacy of Hong Kong's return to authoritarian China.
Many Hong Kongers at the time wanted Britain to grant them full citizenship but China was opposed to the move.
The BN(O) was a compromise, allowing Hong Kongers born before 1997 the right to stay in Britain for six months at a time, but with no working or settling rights.
Now it has become one of the few ways out for Hong Kongers hoping to start a new life overseas as authorities conduct mass arrests against democracy supporters and move to purge the restless city of dissenting views.