About $2.34 billion has already been spent on the new intercity trains,and the government has allocated another $1.2 billion over the next four years.

A spokesperson for Transport Minister Jo Haylen said the budget included additional costs for both the new intercity and regional train fleet projects.

He said the extra cost of the new regional trains reflected what would be needed to support their entry into service,including additional infrastructure enabling works across the network. “The former government needed to increase these budgets to account for additional costs,” he said.

The government has kept an election promise to invest$303 million for rapid bus links to the new Western Sydney Airport from Penrith,Campbelltown and Liverpool. However,the funding is a fraction of Transport for NSW’s previous internal cost estimates of $1.6 billion for the project.

Following a review of the state’s infrastructure by former Roads and Maritime Services chief Ken Kanofski,the government has delayed or altered projects worth more than $2.5 billion.

As previously flagged,a new motorway tunnel in the Blue Mountains has been deferred while the state’s fast rail program has been paused pending the release of a review by the federal government into infrastructure projects.

The state government has committed $770 million to establish an urban roads fund,which is earmarked for 23 projects over the new four years,including improvements to key corridors in Heathcote and Riverstone.

Funding will also go to planning for upgrades for the Fifteenth Avenue transit corridor between Liverpool and the new city of Bradfield near the new Western Sydney Airport.

All up,the budget commits $72.3 billion to new and upgraded transport infrastructure across the state over the next four years,including $7.9 billion for a metro rail line to Western Sydney Airport which is due be completed in 2026.

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