Prime Minister Malcolm Turnbull accuses the Queensland Premier of holding national rail projects hostage, because the Commonwealth would not fund Brisbane's Cross River Rail project.

Today's Queensland budget saw Treasurer Curtis Pitt announce an extra $1.95 billion over forward estimates for the Cross River Rail project, in addition to the $850 million already funded in previous budgets, so works can start as early as the end of this year.

[color=#000000][size=1]PHOTO:[/size][/color] Prime Minister Malcolm Turnbull said the Cross River Rail project business case was still being reviewed. (ABC News: Nick Haggarty)

The Premier said she was still hoping for a federal funding contribution, but Queensland was prepared to go it alone if necessary.

In Question Time today, shadow transport minister Anthony Albanese asked Mr Turnbull why his government would not fund the Queensland rail plan.

"Why is the Prime Minister purporting to support public transport in our cities, while pretending this essential project is not ready to go?" he said.

Mr Turnbull said Labor was too focused on urban projects, while withholding support for national rail plans, like an inland rail line.

"[What about] the inland rail, which the Labor party doesn't have much passion for, and the Queensland Premier wants to sort of hold hostage until there's commitment to the Cross River Rail in Brisbane," he said.

"A vital piece of nation building infrastructure across regional Australia, is to be held hostage until there is a commitment to an urban rail project in the middle of Brisbane.

"And hardly seems to have a commitment to the national interest."

Mr Turnbull rejected claims the project was ready for federal backing, saying the business case was still being reviewed.

"The Cross River Rail project is being considered by Infrastructure Australia now ... and we are awaiting Infrastructure Australia's assessment of the project," he said.

Cross River Rail 'vital for Brisbane's growth'Industry groups from across Queensland have praised the Government's decision to commit to fund the Cross River Rail project.

Transport, construction and health groups have backed the massive injection of funds.