"We want to provide a long-term, sustainable model for KiwiRail."
Prime Minister Bill English said the Government wanted to know if any changes would help KiwiRail stand on its own. He ruled out privatisation.
"Essentially the operating business as I understand it does make money. But the capital requirements to maintain a large rail network are very substantial."
New Zealand First leader and Northland MP Winston Peters said the review showed the Government had "woken up" to the fact rail was needed because of road congestion.
"Remarkably, this dollars-obsessed Government has even hinted at removing the requirement for KiwiRail to be commercially viable and to make a profit, which it is currently required to do by law."
Earlier this month KiwiRail said it could spend up to $50m on new carriages for its tourist trains as it rides the tourist boom. The company is also rebranding its Cook Strait ferry and scenic train services under one brand, The Great Journeys of New Zealand.