The government said foreign domestic helpers arriving in Hong Kong can start working and staying at their employers' homes after a three-day mandatory quarantine at a designated hotel, as a new quarantine rule takes effect on Friday.

Alternatively, employers may arrange their helpers to stay at licensed hotels or guesthouses after they complete their mandatory quarantine.

"In view of the conditions of individual families, the Commissioner for Labour has given in-principle approval for employers to arrange foreign domestic helpers to stay at licensed hotels or guesthouses that are not designated quarantine hotels to complete the four-day medical surveillance and subsequent three-day self-monitoring," the Labour Department said in a statement.

"It is not necessary to make an application to the Labour Department."

From Friday, people arriving in Hong Kong will have to spend three days in hotel quarantine, down from the current seven.

After three nights at a quarantine hotel, arrivals will undergo medical surveillance for four days and will be given an "amber code" on their LeaveHomeSafe app to restrict their movements.

The department said during this period, helpers can conduct daily essential activities of lower risk, such as taking transport and entering supermarkets, but are not allowed to visit high-risk premises involving mask-off or group activities, adding that they are required to take multiple PCR tests.

It also noted that helpers who have already completed three nights of mandatory quarantine before Friday are being arranged to leave the designated hotels in an orderly manner.