Hui was among those who attended a meeting between Hong Kong and mainland experts to facilitate the reopening of borders.

He said one of the essential conditions for reopening will be for Hong Kongers to use a code similar to mainland's health code when they cross the border.

“The code should contain a negative result of nucleic acid Covid-19 test, vaccination record, and proof that one did not contact Covid-19 patients nor visited high risk areas. There should also be information on where the person went over the past three weeks,” he said in a TVB program on Sunday morning.

Hui said he did not know if the code to launch in Hong Kong would record one's whereabouts, or if it would get existing information recorded on their LeaveHomeSafe app. Further discussion with Innovation and Technology Bureau is necessary, he said.

Mainland experts also want Hong Kong to increase the frequency of tests for people who have contact with overseas arrivals from every three to seven days to every other day.

The experts also recommended tightening control over confirmed Covid-19 cases. They should have their health monitored for 14 days even after they test negative of the coronavirus twice.