Co-location arrangement has already been implemented in five ports in China, including one in the West Kowloon Station of the Hong Kong Section of the Guangzhou-Shenzhen-Hong Kong Express Rail Link. The station includes the Hong Kong Port Area and the Mainland Port Area, in which law enforcement personnel from both sides conduct respective clearance procedures for passengers.

Tang said the governments of HKSAR and Shenzhen have agreed to adopt the joint immigration checkpoint at the new Huanggang Port and are considering further implementing a new clearance mode called "collaborative inspection and joint clearance."

Under the arrangement, automatic channels or counters for both outbound and inbound visitors will be set up side by side at the boundary inside a port. Visitors only need to queue up and have their documents inspected once to pass through the immigration facilities on both sides and complete the respective immigration procedures.

It will significantly improve the entire clearance experience and efficiency by avoiding visitors' inconvenience of having to travel with luggage between the two port buildings for immigration clearance, Tang added.

The security chief said the SAR government would explore adopting a "co-location arrangement" and "collaborative inspection and joint clearance" mode in planning the redevelopment of the Sha Tau Kok Port and the development of new border control points in the future.

Responding to whether there is a plan to implement the co-location arrangement or even the joint boundary control system at the Hong Kong International Airport, Tang stressed that it would involve different legal and implementation issues and must be carefully considered.