The Hong Kong government and MTR Corporation Limited executed a project agreement for the full Northern Link (NOL) Project on November 10, after the Chief Executive in Council approved the financial arrangement for Part 2, according to a government release. The Main Line and Spur Line are now reported to be fully in the construction stage, with a target of commissioning simultaneously by 2034 or earlier.

The Main Line involves a 10.7-kilometre underground railway and five stations, with interchange stations at Kam Sheung Road and Kwu Tung linking the Tuen Ma Line and East Rail Line respectively. The Spur Line involves about 6 kilometres of underground railway branching from San Tin Station, including a Shenzhen section of approximately 1.1 kilometres, and stations at Chau Tau, the Loop and Huanggang Port. Officials said peak-hour travel between Kam Sheung Road and Kwu Tung would fall from the current 60 minutes to 12 minutes.

The estimated capital cost for the entire project is about $86.2 billion in July 2025 prices, which the government said is 28 per cent below the original estimate. Sites in Ngau Tam Mei, San Tin, Kwu Tung North and Au Tau were approved for residential and commercial development under the "Rail-plus-Property" model.