Negotiations between the NSW government and rail unions have broken down, after the finance minister cancelled talks and warned unions against engaging in "industrial chaos".
Transport Minister David Elliott recently brokered a detente with the Rail, Tram and Bus Union, after a long-running dispute led to a government-led shutdown of Sydney's rail network earlier this year.
The union says five weeks of intensive negotiations and progress could now be undone with a suggestion the government is playing tactics.
The RTBU proposed an operating model for New Intercity Fleet trains, and was supported by Sydney Trains' senior management team, Transport for NSW and the Minister for Transport, Secretary of the RTBU NSW Alex Claassens told AAP.
"You can imagine our shock when we walk into a room and (Finance) Minister (Damien) Tudehope turns around and says to us, 'I'm going to put the submission up to cabinet next week, but I'm not going to support two main key issues'."
Mr Tudehope walked away from making fixes to the NIF train, which the union believes is unsafe, and finalising one workplace agreement for both Sydney and regional trains, according to Mr Claassens.
"We now see what he's trying to do, of course, was force us into a position where we got angry and started taking industrial action again," he said.
"Which means that he would then try and take us down the (Industrial Relations) Commission again to try and cancel our industrial action."
Mr Tudehope on Thursday said he would not support any union demands that delayed the rollout of the NIF, and he would take action to protect commuters if pushed.
"I want to commend the good work done by union and rail officials in working through more than 300 claims originally put forward by the unions over the last six weeks of intensive bargaining," Mr Tudehope said in a statement.
"I am confident that we will soon come to a fair and reasonable offer for rail workers."
He said the NIF were safe, world-class trains and "they should be in operation today".
"The refusal by union leadership to operate these trains is further evidence of their collusion with NSW Labor," Mr Tudehope said.
"I urge the unions to consider their position carefully and not to resort to extreme industrial action while the government's offer for rail workers is finalised.
"If industrial chaos is the path that NSW Labor and the unions want to go down, I will not hesitate to take action in the Fair Work Commission to protect commuters."
Opposition Leader Chris Minns asked Mr Elliott about media reports indicating the government had made significant progress on the NIF.
"Yet moments ago the minister for finance (Damien Tudehope) cancelled all talks (with the union)," Mr Minns said during Question Time on Thursday.
"The rail negotiations have been going on for six weeks," Mr Elliott said.
"We're very close to agreeing on most matters, but I'm certainly not going to be providing to the leader of the opposition about how those negotiations are going - simply because I know the leader of the opposition has been front and centre in every industrial action, and every industrial dispute.
"I will continue to work with the unions to make sure that ... the welfare of their members, and the welfare of Transport For New South Wales continues to be front of mind."
Shadow Transport Minister Jo Haylen accused the government of trying to cause chaos across the rail network for political purposes.
"This government shut down our entire train network, inconveniencing millions of commuters right across greater Sydney just to make a political point," Ms Haylen said.
"It's playing politics with our transport network and it is inflaming an industrial dispute which the government is meant to be solving through negotiations."
