Last week it was revealed that a government document mentioned that a tunnel from Thirroul to Waterfall could cut around 22 minutes of travel time from Wollongong to Sydney.

However, Mr Constance this week said the tunnel rated only a small mention and was not the main focus of the report.

“It was a broad consultants report on the corridor strategy and buried on page 30-odd was a reference to Thirroul tunnel,” Mr Constance said.

“[Former NSW Premier] Bob Carr had a go at back in 2003 and then realised it was not feasible to do it.”

Mr Constance said the aim of the report was to place all options for the South Coast line on the table.

“What we want to do is look at everything,” Mr Constance said.

“That report looked at everything through to timetabling, through to major infrastructure builds. It was a combination of things –  it wasn’t a single Thirroul tunnel report.

“I’m happy to look at everything we can in terms of trying to improve travel times for everyone in the region. We want to try and speed up the travel times.”

However, a tunnel at Thirroul tunnel is not on the government’s agenda, as the estimated cost would be around $3 billion.

This week on ABC Illawarra Mr Constance described building a tunnel as a “pixies at the bottom of the garden stuff” and said “it’s not possible”.

This did not stop NSW Greens MP and Transport spokeswoman Mehreen Faruqi calling for the release of both this document and papers relating to the F6 extension.

This comes after concerns the government was opting for road over rail.

Several members of the government have denied any push to build road projects at the expense of rail.

“If rail options are so unviable, why doesn’t he release the full documentation, including business cases, of the F6 and the Thirroul tunnel and let the public decide,” Dr Faruqi said.

“It shows how little the NSW government values public transport when it refuses to properly investigate viable transport alternatives but there are rivers of gold for yet another toll road.”