In the weekly press briefing on Tuesday, Lee said he believed the reverse quarantine scheme would meet the requirements of the mainland’s anti-epidemic standards and would not increase the risk of imported cases.

“I hope the scheme can continue to operate regardless of the situation of the epidemic,” he said.

China's current quarantine policies for travelers from Hong Kong include seven days of compulsory quarantine in designated hotels and three days of self-surveillance home quarantine.

The reverse quarantine scheme plans to allow travelers entering the mainland to complete this “3+7” process in Hong Kong.

Referring to the Shenzhen government's decision to reduce the entry quota to 1,000 per day, Lee emphasized reverse quarantine would be stable once launched.

He called on the city to increase the vaccination rate, noting that authorities would listen to the views of different sectors to improve the disease prevention measures.

When asked about unvaccinated mainlanders being allowed to enter local vaccine pass premises like restaurants, Lee said the arrangement has been in operation for a long time, and China is among the places around the world with the lowest Covid risks.

According to the arrangements for Provisional Vaccine Pass, inbound travellers who arrived from the mainland or Macao after May 1 that were not required to undergo compulsory quarantine could obtain a Provisional Vaccine Pass. The provisional pass is valid within 180 days from arrival.

However, overseas travellers and locals are barred from entering high-risk premises if they are unjabbed.

University of Hong Kong's microbiologist Ho Pak-leung called for authorities to extend the vaccination requirement to the temporary Vaccine Pass.