The move comes days after Macau started to unwind stringent anti-Covid rules, including the resumption of travel to Zhuhai without quarantine from Aug 3.

The announcement comes after the city government said that people could enter the neighbouring mainland Chinese city of Zhuhai without quarantine

Health authorities will require residents to wear masks when they go out and must show a negative coronavirus test within three days to enter most venues.

The tally of infections since June 18 stood at 1,816, the government said in a statement, as the city grapples with the fast-spreading Omicron variant for the first time.

While casinos will reopen, there will likely be no business for several weeks, executives and analysts say, with many Covid rules set to remain in place.

Although more than 90% of residents are fully vaccinated against Covid, this is the first time Macau has had to grapple with the fast-spreading Omicron variant.

A Covid-19 outbreak has meant full-scale closure for the former Portuguese colony's six casinos - the only places in China where gambling is legal.

Casinos were last closed in Macau in February 2020 for 15 days in an unprecedented move to fight the virus.

Authorities have set up a makeshift hospital in a sports dome near the city's Las Vegas style Cotai strip and have around 600 medical workers from the mainland assisting them.

One Central shopping mall will be shut for one week, while more than a dozen other zones or buildings have also been ordered to close, authorities say.

At least 16 other buildings across the special Chinese administrative region are also locked down with no one allowed to exit or enter.

While Macau, a Chinese special administrative region, has not introduced a full scale lockdown seen in mainland Chinese cities like Shanghai, the city is already largely closed.