The Victorian Greens have released a State Government advisory indicating its order for Regional Rail Link trains falls well short of demand.
The Government has refused to comment on figures in a V/Line document suggesting a significant shortfall in an order for regional trains.
The Greens obtained the V/Line advisory under Freedom of Information.
It advisory recommends the Government order 67 new carriages for its Regional Rail Link project to cope with growing service demand.
But the Government has only ordered 40.
The Premier, Ted Baillieu, would not elaborate on the Government's decision.
"Spare me, we've just ordered 40 new carriages, and I've got to say we have just ordered 40, and I'll leave it to the Greens to deal with that issue," he said.
"The previous Government hadn't made that order, we have, and we've got good value for it," the Premier said.
The Greens say the Government has failed to order enough trains to meet demand for the Regional Rail Link.
Greens MP Greg Barber says the figures show it will be standing room only on regional rail for a long time to come.
"It means things like people from the Latrobe Valley getting pushed off trains in Dandenong and having to move to the suburban system, it means places like Shepparton, Warrnambool, Ararat, can forget about even one extra train service," he said.
Mr Barber says regional train users have been let down.
"We've seen double-digit growth on V/Line over the last 10 years, and I predict that it'll be something very similar over the next 10.
"That means we need a short, medium and long-term plan but all we've got really is a secretive and furtive memo from V/Line to the Government," he said.