Most non-residents, including tourists, will be banned from entering Hong Kong for 14 days starting tomorrow, following a spike in the number of new coronavirus cases fuelled largely by people returning from overseas.
Residents of mainland China, Taiwan and Macau who have recently been overseas will also be barred from entering the city.
But those who enter Hong Kong directly from the mainland, Taiwan or Macau will be allowed in.
These moves, announced by Hong Kong's Chief Executive Carrie Lam yesterday, are the toughest measures yet against the coronavirus pandemic, which is into its second wave in the city.
Currently, everyone from overseas - including mainland residents - entering Hong Kong has to undergo a mandatory 14-day quarantine, except people from Taiwan and Macau.
However, from tomorrow, those from Macau and Taiwan have to do the same.
Hong Kong residents who return from Europe and the United States will have to undergo tests to determine if they have the coronavirus, while the city's international airport is suspending all transit services for two weeks.
The government will introduce laws as well to prohibit the sale of alcoholic beverages to all licensed eateries, restaurants and pubs, said Mrs Lam, adding that about 8,600 of them are expected to be affected. Supermarkets and alcohol retailers are not covered by the ban on sales.
She did not specify when the booze ban would be rolled out, but said the emergency legislation was being drafted.
"Sometimes when you go out to eat at a restaurant, you can sit farther away from others and can split dishes to eat... But in bars, sometimes when people drink more, there may be some intimate acts," she added, in explaining the move.
At the hour-long news conference, Mrs Lam became visibly emotional as she urged residents to abide by quarantine measures so that they do not affect the rest of the community, and to "fight the battle seriously".
"The situation has been changing rapidly. Throughout these two months, we have gone through many stages. Efforts have been effective in preventing a major community outbreak. The number of confirmed cases in Hong Kong is lower than that of many overseas countries. This achievement is hard-earned," she said in her plea.
The Bar and Club Association, comprising 300 members, slammed the government for unfairly targeting the industry while failing to enforce more stringent quarantine measures.
Association vice-chairman Wing Chin reportedly described her explanation that drinking in bars could prompt intimacy as "a joke".
On Sunday, the government announced 44 confirmed cases - the second-highest surge in daily confirmed cases since the coronavirus outbreak started.
The health authorities said yesterday that the number of confirmed cases went up by 39 to 356, including four who have died. Of the 39, 30 had travelled overseas recently.