Tolls on Melbourne roads could have been raised to pay for the East West Link.
The East West Link business case, to be released on Monday, reveals tolls on stage one of the stalled tunnel would not have covered its ongoing costs, News Corp Australia reports.
It says road operators Transurban and ConnectEast raised the prospect of increasing tolls on their existing roads with the Napthine government before the business case was completed.
"Adjusting pricing arrangements on these existing toll roads would increase the total funding available for the Road Link, as well as establish a fair and efficient toll regime across Melbourne's freeway network," the business case reportedly argued.
A state government spokesman said he could not confirm the documents were real and they had not been released by the government.
The stalled $6.8 billion road tunnel project was a controversial issue at the November 29 state election, after Labor promised not to build it.
Premier Daniel Andrews said on Sunday he would not comment on whether the East West Link business case was done with the due diligence found on other Victorian government projects.
"I have my doubts but I'll leave you to make those judgments when you look at those many, many pages of documents," he told reporters.