Chief Executive Carrie Lam on Saturday officiated at the opening ceremony of the East Rail Line cross-harbour extension, a day before the new route is open to the public.

To celebrate the opening of the new extension, a special train will depart from the Exhibition Centre station at 5:25am on Sunday.

The extended route will allow commuters to make a direct 46-kilometre journey from Sheung Shui to Admiralty in just about 40 minutes, without having to switch lines.

Lam was among the first to ride a train from Hung Hom to the newly-built Exhibition Centre station, along with others such as transport chief Frank Chan and the chairman of the MTR Corporation, Rex Auyeung.

Speaking at the launch ceremony, the CE said she believes the link will boost the city’s development and be immensely popular among Hongkongers.

"The East Rail Line will closely link up the Victoria Harbour Metropolis, which is dubbed as an international financial centre, and the proposed Northern Metropolis, which will make Hong Kong a global innovation and technology hub. With that, we can achieve the vision of the two metropolitan areas in the north and the south advancing side by side and complementing each other," she said.

She added that the government is looking into possibly extending the line to Luohu district in neighbouring Shenzhen to connect with the Greater Bay Area.