The move will take effect this weekend and continue through Jan. 21, with a ban on passenger flights from Australia, Canada, France, India, Pakistan, the Philippines and Britain.
"Those who have stayed in such places for more than two hours will also be restricted from boarding a passenger flight for Hong Kong in order to stop relevant people from traveling to the city via transit," wrote news.gov.hk, an online news platform operated by an editorial team of the government's Information Services Department. "The government said the new measure is extremely stringent and will inevitably affect the return journey of a number of Hong Kong residents in these eight countries."
In addition, Hong Kong Chief Executive Carrie Lam said that there would be a curfew on restaurant dining, with customers not allowed to do so after 6 p.m.
That change will last for two weeks starting on Friday, and arcades, bars and beauty salons are also required to close during the same period.
"We have to contain the pandemic to ensure that there will not be a major outbreak in the community again," Lam told reporters. She noted that Hong Kong is "on the verge" of another surge.
Hong Kong has reported 114 omicron variant cases as of Tuesday, with most being imported.
On Tuesday, the city reported its first untraceable COVID-19 case in nearly three months, which authorities said was likely caused by the variant of concern.
Many new omicron cases have been linked to several Cathay Pacific Airways crew members who broke isolation rules and dined at restaurants and bars in the city before testing positive.
On Wednesday, Hong Kong held 2,500 passengers on a cruise ship for COVID-19 testing after health authorities said nine passengers were linked to an omicron cluster and ordered the ship to return.
The Royal Caribbean’s Spectrum of the Seas ship, which departed on Sunday, returned a day early and passengers were held onboard.
Royal Caribbean said the guests were immediately isolated and all tested negative.
The company said it was working closely with authorities and that guests on the ship would receive a 25% refund on their cruise fare.
The ship's next sailing on Thursday was also canceled because the crew must undergo testing. Those guests will also receive a full refund.
According to the Government of Hong Kong Special Administrative Region COVID-19 Dashboard, Hong Kong has reported more than 12,700 confirmed cases of the virus as of Tuesday, including 213 deaths.
The Associated Press contributed to this report.