Eight Victorian industry groups are backing the East West Link, saying it will be essential to the state's long-term economic development.
A statement by the Victorian Employers' Chamber of Commerce and Industry (VECCI), released on behalf of the groups, says the project's first stage will be a vital cog in the state's road and freight network.
The groups, which represent more than two million members, say the link should be built if Victoria is to keep its position as Australia's freight logistics capital.
"The only way Victoria will be able to manage this logistical challenge is if a pipeline of major projects such as East West Link, Metro Rail and the North East Link are built," they say in the statement.
The groups say the cost of congestion to the Victorian economy is forecast to rise from $3 billion to more than $6 billion by 2020 and building the East West Link will be critical to ease that.
They say the project will also boost productivity and reduce business costs.
"Our organisations consider the construction of the East West Link to be vital to the long-term health of the Victorian economy and the millions of workers it supports."
The groups include the Australian Logistics Council, Australian Industry Group, Infrastructure Partnerships Australia, Master Builders Association of Victoria, Property Council of Australia, Royal Automobile Club of Victoria and Victorian Automobile Chamber of Commerce.