Vic West Gate Bridge project under way

A $500 million plan to get trucks off Melbourne's West Gate Bridge is under way.

Expressions of interest have been called for the first stage of the West Gate Distributor, which the government says will take 5000 trucks a day off the bridge.

It will direct them to the Port of Melbourne on a dedicated road, easing congestion for city-bound traffic.

Roads Minister Luke Donnellan said expressions of interest were open for the $40 million first stage.

"With the West Gate Distributor, the morning drive from Ballarat, Geelong and the western suburbs will be faster and safer," Mr Donnellan said on Wednesday.

The contract for the first stage is expected to be awarded midyear, and construction will begin by the end of the year.