The government said on Sunday that it's trialling an upgraded electronic health declaration system from Thursday under which inbound travellers will have to complete an electronic health declaration form and get a QR code before boarding their flights to Hong Kong.

If the trial is a success, it will phase in the new system next month, it said.

"Completing the health declaration prior to boarding allows smoother arrival quarantine procedures for inbound persons," a government spokesperson said in a statement.

"It will also facilitate the gradual introduction of electronic processing of arrival quarantine procedures, thereby reducing the need for manual processing and hence the waiting time and bottlenecks."

Under the existing quarantine rules, incoming travellers have to complete health declarations and undergo the "test-and-hold" procedures at the airport.

The government said most travellers now use the electronic declaration system which was introduced in June 2020, but some still filled out health declarations on arrival, delaying other visitors.

It said the new system will come into effect from Thursday, and everyone flying to Hong Kong will have to fill out the form electronically and present the QR code before boarding their flights.

It said the health declaration QR code will be valid for 96 hours, which means inbound travellers can submit the declaration form as early as three days before their scheduled arrival time in Hong Kong.

The government said it plans to upgrade the electronic health declaration system and the functions of the QR code in August once the trial is successfully completed.