Former deputy prime minister John Anderson has warned the Federal Government it must allocate more than $1 billion in the budget to fund Inland Rail, or dump the scheme altogether.

Mr Anderson said the farm and business sectors want certainty the Government is committed to completing 1,700 kilometres of track connecting Brisbane and Melbourne, and linking south-east Queensland to Adelaide and Perth.

Farmers have lobbied governments to build an inland rail network for decades and argue the current system costs them hundreds of thousands of dollars each year because it is inefficient and slow.

The former Labor government committed to the Inland Rail project and when the Coalition came to power it promised to fast-track it.

But Mr Anderson is disappointed there has not been any new funding since 2013.

"If the Government doesn't think [Inland Rail] ought to be, then it should kill it [and] end any uncertainty," he told the ABC.

"This sort of half pregnant stuff that we get... we're seeing too much of that from governments."

Last year he wrote a report for Government which found that the project would create 16,000 jobs during the construction phase, and that eastern Australia will become clogged up with heavy multi-carriage trucks if the network is not built.

"I think people think government is losing its ability to make clear-cut decisions, and they want clear-cut decisions. And I can tell you something else: Australians get that infrastructure creates jobs and wealth and a stronger economy," Mr Anderson said.

"Whether it's done by 30-year bonds or however it's done, it's never been cheaper to borrow and there are times where even if you have to borrow, then it makes sense [because] you grow a bigger economy."

Current system costing farmers

Australia's current rail system costs grain farmers like Dan Cooper, from south-west New South Wales, hundreds of thousands of dollars each year.

"Rail being the core component of getting grain or produce to port, you know, I think we're the second highest cost producer in the world," he said.

Mr Cooper said the inefficient nature of the system leaves Australia's agricultural sector at a significant disadvantage to competitors like Canada and the United States.

"So when you look at our $20 freight advantage into Asia just by proximity, that is evaporated through inefficient supply chains," he said.

He said the Government should look to the private sector for co-investment in the project and was adamant the results would be worthwhile.

"I'm sure when they were building a dam up in the Abercrombie (for the Snowy Hydro Scheme) they were thinking, 'what the hell's this going to do?', but when you look at what it's done to those regional communities, it's just quite amazing and that's how it needs to be viewed," he said.

"It's a long-term strategy and again, that's the shortcoming of the budgets we've seen over the decades. We don't see that intergenerational view of what big infrastructure tickets can bring to the economy."

The Government is considering allocating more money to Inland Rail but it is unclear how big the commitment could be.

When questioned about it by the ABC in Sydney, Deputy Prime Minister Barnaby Joyce said: "I know how much has been allocated... and I'm not telling you."