The Victorian Government has announced it will begin work on one of Australia's largest infrastructure projects, the Melbourne Metro Rail Project.

The new Melbourne Metro Rail line includes a nine-kilometre twin rail tunnel from Melbourne's south, under the CBD, through to the university and health precinct in the city's north. It will include five new and expanded underground stations.

Construction of Melbourne Metro Rail will allow an additional 19 train services to operate across the network during the peak, which is the equivalent of 20,000 extra passengers. The project will significantly increase the capacity of the whole public transport system in Melbourne, allowing for additional trains and paving the way for the construction and extension of train lines in other growth areas.

The project, which will create 3,500 jobs during its construction, will transform Melbourne's public transport into a world-class system, comparable with Hong Kong, Paris and London.

The Victorian Premier, Daniel Andrews said that the project would result in "more services, fewer delays and better public transport."

With the project currently in the planning and pre-construction phase, there will be significant opportunities for private sector involvement in the transport infrastructure project, including delivery, financing and urban precinct development. An Expression of Interest will be released in 2016 with major construction expected to commence in 2018.

The announcement indicates the Victorian Government's commitment to increasing jobs and developing major projects that benefit the State, and a transformed Melbourne Metro Rail system will serve to enhance Melbourne's reputation as the most liveable city in the world.