"Significant concerns" have been identified in a major rail project to complete Australia's national freight network.
But the issues outlined in the report from an independent review will not be made public until the government has developed its responses.
Transport Minister Catherine King and Finance Minister Katy Gallagher on Monday confirmed the Inland Rail project review had been delivered to the government, noting its findings were troubling.
"It reveals significant concerns about the governance and delivery of Inland Rail," a joint release said.
The Inland Rail project will establish a 1700-kilometre rail link between Melbourne and Brisbane, running through regional Victoria, NSW and Queensland to complete the national rail network.
An independent review was ordered in October over concerns the project, which was originally due to cost $4.7 billion and has a budget of $14.5b, could end up costing more than $20b.
The review, led by former Sydney Water chief executive Kerry Schott, looked at "planning, governance and delivery" of the project including its route, consultation and where intermodal terminals should be built.
Transport Department secretary Jim Betts told a Senate estimates hearing on Monday the independent review was ordered to provide clear guidance on potential cost blowouts and delays to the complex project.
"There (were) clear indications of significant emerging cost risk and risk to delays, questions marks around the governance of the project," he said.
Assistant Regional Development Minister Anthony Chisholm said the government would release its findings at the same time as its response.
"We're considering the report and we'll respond in due course," he said.
Peter Wilson, who chairs NSW Farmers' inland rail task force, said it looked forward to reading the review after raising concerns about the project's delivery and protocols for dealing with property owners along the rail route.
The group had been working with mediators over the last three months to develop new systems, he said.
"Landholders were concerned about things such as contractors appearing unannounced, disagreement on land values, fencing standards and generally the manner of dealing with (Australian Rail Track Corporation)," Mr Wilson said.
"It is important that Inland Rail delivers good economic outcomes for regional New South Wales, and that landholders are treated fairly and respectfully."
Construction on the Inland Rail project began in 2018 and is due to be completed in 2027. It is expected to upgrade 1100km of existing rail infrastructure and build another 600km of rail tracks.
