The extension of the Tung Chung line formed part of the third phase of land reclamation in Victoria Harbour on Hong Kong Island's northern coast.

[2] On 21 February 2013, the Highways Department launched stage two of public consultation of Our Future Railway, and proposed two schemes for the North Island line.

The existing Tung Chung line would be extended along the northern coast of Hong Kong Island, with Tamar, Exhibition Centre, Causeway Bay North and Fortress Hill stations along the route.

In addition, the maximum train frequency between Fortress Hill and Chai Wan stations, which would be served by the Tung Chung line, would have to reduce by 8 trains per hour because the service frequency of the Tung Chung line is restricted by the capacity of the Tsing Ma Bridge.

According to the "Railway Development Strategy 2014" document, the government opted for the interchange scheme because its construction cost and difficulties are lower and it does not interfere with the commuting patterns of current Island line users.