Under the plan, 30 kilometres of extra lanes will be built along the Monash freeway between EastLink and Clyde Road in Berwick.

Between EastLink and the South Gippsland Freeway the road will expand from four lanes to five in each direction.

Further east of the road will grow from two to three lanes.

Officials say it will make the trip quicker for 200,000 commuters every day.

The business case will be submitted to the federal government this week and Mr Andrews said the project would deliver $4.20 of benefit for every dollar spent on the project.

Under the project better traffic management of on-roads, which are frequently congested, will also be installed.

In October, federal Minister Greg Hunt called for a Monash freeway expansion but Premier Daniel Andrews said work on the plan had been going on for nearly all of 2015.

The project will be put out to tender next year, with construction to begin in 2017 and completed in 2018, when the next state election will be held.

Speaking in Hallam on Sunday, Mr Andrews said he wanted the federal government to partner on the project.

He said "logically" money from the $1.5 billion of Commonwealth funds for the dumped East West Link could be used to fund the expansion.

Talks have begun with the federal government and infrastructure Australia, Mr Andrews said.

"This is an investment, it is not a cost, it is an investment in better safety, cutting travel times and making sure the South-Eastern suburbs can continue to  be such a strong and great place to live."

He said money could be used from the $1.5 billion allocation for the East West Link if the project stacked up and the two governments could work together.

Mr Hunt said that the project was overdue but welcome and that the government was willing to work with the state government and examine the details of the project.

"There is no question that the general upgrade in the area is needed and in the absence of the East West Link it is the number one immediately ready project in Victoria," Mr Hunt said.

Infrastructure Minister Warren Truss' spokesman said the government would welcome the business case.

"It will have to go to Infrastructure Australia for assessment and then go through the normal process," he said.

But state Opposition Leader Matthew Guy said the project was lacking detail.

"This is just yet another thought bubble by a government that has limited infrastructure vision for this state," Mr Guy said.

"When on earth is Daniel Andrews going to give us some details about how he wants to fund all the things he is announcing."

Federal Liberal MP Alan Tudge, who represents Aston and has pushed for extra lanes, said the government would like to see the specifics of the proposal.

"It is a car park in the mornings and needs extra capacity, but the question is whether what's proposed is enough to make a serious difference," Mr Tudge said.

The business case has been developed in parallel with the assessment of Transurban's Western Distributor project, but would proceed regardless of the success of that proposal.

The Premier said he hoped to make announcements regarding the Transurban proposal in the coming weeks.

There will be some "inconvenience" for motorists during construction which could compound other congestion caused by level crossing removals across Melbourne during the same period.

The project also includes new ramp signals, and will create the longest stretch of managed freeways in Australia, from Werribee to Pakenham.

Mr Andrews said European Union officials are studying the Monash Freeway's traffic management systems.