"I will pursue the principle of 'bringing forward infrastructure construction and increasing development capacity' as mentioned in my election manifesto," John Lee said.

The Northern Metropolis Highway will facilitate east-west connectivity in the New Territories North between Tin Shui Wai in the west and Kwu Tung North in the east via San Tin and expand transport capacity in the new metropolis.

The Shatin Bypass - a new north-south trunk road connecting Tai Po and Kowloon West - will provide residents of the New Territories East a faster route to urban areas and relieve pressure on Tolo Highway.

Construction of the Tseung Kwan O-Yau Tong Tunnel will synchronize with the future development of Area 137 in Tseung Kwan O.

For railways, the Hong Kong-Shenzhen Western Rail Link will connect Hung Shui Kiu with Qianhai to facilitate travel between Hong Kong and Shenzhen and promote the SAR's Greater Bay Area integration.

Since the Western Rail Link crosses over to the mainland, construction costs will be split between local and mainland authorities.

The majority government-owned MTR Corp will be invited to contribute to the construction work, a source said, adding that there is also a "high chance" authorities will tender out the work to overseas independent railway construction companies.

The construction of the Central Rail Link - the 12th railway line - will connect Kam Tin in Yuen Long with Kowloon Tong via Kwai Chung, easing pressure on the Tuen Ma Line.

The Tseung Kwan O Line Southern Extension which extends the MTR line southbound to Area 137 will enhance transport facilities in the vicinity.

A blueprint for the three railway lines including a construction timeline will be released by the end of 2023, the source said.

The East Kowloon Line, first proposed in September 2014, will utilize a trackless design, a source said, adding that a construction timeline will be announced in the first half of next year.

The new system will connect Sau Mau Ping, Shun On, Shun Lee and Choi Wan with the existing Choi Hung station.

MTRC welcomed the chief executive's proposals to extend the railway network.

"The corporation will proactively leverage our expertise in railway development and operations in promoting the sustainable development of Hong Kong in support of the government's strategy of using railways as the backbone of the public transport system," a spokesman said.

Lee said Northern Metropolis will be a "new international I&T [innovation and technology] city," integrating quality life, new economies and culture and leisure.

Authorities will maximize use of land resources in Northern Metropolis by adopting higher plot ratios - 6.5 for residential sites and 9.5 for commercial sites.

The government will also begin planning for the construction of cultural facilities, post-secondary education institutions, major sports facilities, hospital networks and government facilities in the area.

Designated government offices in the city's central business districts will be relocated to Northern Metropolis, including nearly 40 percent of the office floor area at the Queensway Government Offices.

A steering committee, led by Lee, will be established to strengthen governance over the development of the area. An advisory committee will be chaired by Financial Secretary Paul Chan Mo-po and comprise various experts and stakeholders.