China's top legislature began deliberations on Friday on a joint checkpoint arrangement for the express rail link connecting the Hong Kong Special Administrative Region with Guangzhou, Guangdong province.

The co-location plan addresses new issues that have come up in the implementation of the "one country, two systems" policy, and endorsement by the Standing Committee of the National People's Congress would give the plan binding force, Zhang Xiaoming, director of the Hong Kong and Macao Affairs Office of the State Council, said during an explanation to the legislators on Friday.

The resolution is scheduled for a vote on Wednesday. It is the second step in a three-step process for the Guangzhou-Shenzhen-Hong Kong Express Rail Link (XRL), a much-anticipated piece of infrastructure that will merge the Hong Kong SAR into the Chinese mainland's high-speed rail networks.

An agreement to launch a joint checkpoint service at West Kowloon Station on the Hong Kong section of the XRL was signed on Nov 18, between the mainland and the Hong Kong SAR, signaling the start of the process.

If the national legislature approves the plan, the region could implement it through local legislation - the last step in the process.

The co-location arrangement, which is key to the XRL, will save time and add convenience for passengers crossing the boundary. It will enable one-stop clearance and boundary control by allowing customs from both sides to perform their duties in accordance with their respective laws at their designated areas inside the West Kowloon Station.

Introducing the plan during a panel discussion on Friday afternoon, Shen Yueyue, vice-chair of the NPC Standing Committee, said that the co-location arrangement offers mutual benefits for Hong Kong and the mainland, and will surely bring new economic opportunity to the SAR and play an important role in its stability and prosperity.

Ambrose Lee Siu-kwong, a Hong Kong deputy to the NPC and former security secretary, lauded the better connection with the mainland offered by the proposal.

The 26-kilometer-long XRL, which expected to be opened in the third quarter of next year, will shorten the commute between Hong Kong and Guangzhou from two hours to less than 50 minutes, enabling more efficient exchanges within the 11-city cluster of the Greater Bay Area.

Lee, who witnessed a juxtaposition plan being implemented at the Shenzhen Bay control point 10 years ago, said there were concerns and questions over the arrangement then, but a decade later it is clear that the co-location arrangement has deepened exchanges between Hong Kong and the mainland.

Cao Yin contributed to this story.