Minister Jenny Aitchison non-committal on highway tunnel during Central West visit

Meanwhile, Transport for NSW is looking ahead to the post-race exodus from Bathurst in a week's time and is warning of possibly holding traffic at the base of Victoria Pass to avoid vehicle breakdowns in queues up the mountain.

Ms Aitchison was in Bathurst recently to mark the switch to new lanes on the upgrade of the highway between Kelso and Raglan.

But after a chaotic 24 hours over the Blue Mountains a few days before - when the Great Western Highway was closed for almost a day and traffic redirected to Bells Line of Road had to squeeze through a section that was reduced to one lane - Ms Aitchison was also questioned about the on-again, off-again proposed tunnel from Little Hartley to Blackheath.

The tunnel had moved to environmental impact statement stage under the Coalition state government, but the incoming Labor state government took $1.1 billion committed to the project and reallocated it, including to roads in western Sydney.

Labor argued the tunnel had no business case and was many billions short of the money needed to complete it.

Former Regional Transport Minister Sam Farraway, however, said the plan all along had been for the tunnel to be co-funded with the Commonwealth in a 20-80 state-federal split.

While she was in Bathurst to mark the latest stage of the Kelso to Raglan project, Ms Aitchison was asked whether the NSW Government was willing to fund its share of a future tunnel.

"We will be looking at what the outcome is of the federal review [into the overall proposed Great Western Highway duplication from Lithgow to Katoomba]," she said.

"We've got our own state review that's going on there.

"This is a project that has been talked about for many decades. We have to look at what is the best way to achieve the outcome that's required.

"Is that a tunnel? Is that a duplication? Is that using another route?

"We have to look at all of the options for east-west connectivity across the Blue Mountains."

Asked how highway upgrades either side of the proposed tunnel could be completed if it wasn't certain that the tunnel was going to go ahead, Ms Aitchison said "that's why we're taking the time to do a full corridor assessment, to make sure we have all of the issues addressed before we start making commitments".

"That's why it would be very wrong of me to stand up here today and say we're going to do this or we're going to do that because we need to have a full assessment," she said.

"We've been in government for six months and we've got a former government that was in government for 12 years and couldn't quite get it off the ground.

"We need to make sure we're doing the right thing for the communities, for the freight operators, for the producers and all the people that are involved in this."

Small duplications of the highway at Medlow Bath and at the Coxs River Road intersection are going ahead, but the more ambitious duplications from Katoomba to Blackheath and from Little Hartley to Lithgow have been on hold since the new Albanese government deferred Commonwealth funds.

Ms Aitchison, as a shadow minister, was in Bathurst in the lead-up to the March state election and addressed Labor's position on the tunnel then.

She said at the time that her party wants "to do this once and we want to do it right and that is why we have asked the community to bear with us; we want to have a pause on this so we can do it properly".

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