VICTORIAN Planning Minister Matthew Guy this week unveiled a new vision for Melbourne's central business district that could result in a major enlargement of the capital city zone.

Under the proposal, the capital city zone would expand beyond the Hoddle Grid – created in 1837 and covering the area from Flinders Street to Queen Victoria Market, and from Spencer Street to Spring Street – as well as Southbank and Docklands.

Major opportunities would be made available in Fishermans Bend and E-Gate on the city's western edge, St Kilda Rd in the south and towards Melbourne University on the northern side.

Mr Guy stressed the proposal was a long-term vision – from 20 to 50 years – that needed bipartisan support and was a prelude to consultation on the new Metropolitan Strategy that would be taking place over the course of the year.

The Minister said the proposal responds to community concerns about high rise towers dominating quiet suburban streets by concentrating higher density development in the inner city to take growth pressure off Melbourne's existing suburbs.

"Concentrating high rise, high density growth takes development pressure off existing suburbs and can maintain liveability in existing residential areas while providing a large, vibrant heart to a growing central city area," Mr Guy said.

He also said the proposal acknowledges and caters for the significant growth that has occurred in Melbourne since the Hoddle Grid was first laid out.

"With a population of four million and growing, we need to have a vision for the central city that matches our growth. We know we cannot only expand in the outer suburbs, but need to also extend the beating heart of the city," Mr Guy said.

"This proposal could cement Melbourne as the best CBD for growth and investment opportunity in Australia. Maintaining our advantage is vital for retaining important construction jobs, as well as an affordable city for residents and businesses."