The NSW transport and finance ministers will attend an emergency meeting with the Rail, Tram and Bus Union as they seek to avoid industrial action slated for next week.

Finance Minister Damien Tudehope and Transport Minister David Elliott are expected at the 5pm Friday meeting after one scheduled for the morning was cancelled.

Train drivers will drive slower and refuse to operate foreign-built trains as part of four days of industrial action, announced after the cancellation of the 9am Friday meeting.

Union secretary Alex Claassens said he was told the morning meeting had been cancelled about 10pm on Thursday while involved in the Vinnies CEO Sleepout. He said he was given no explanation.

Transport for NSW notified the union on Friday afternoon of a meeting at 5pm. It gives the state government one last chance to halt industrial action scheduled to begin Tuesday.

Mr Claassens said the government would have to agree to alterations to the new intercity fleet trains, the first of which was delivered in 2019 but has never gone into service.

Treasurer Matt Kean said in May it was costing the government about $30 million a month to store the trains.

Mr Claassens said he had been tipped off prior to the budget that a $300 million line item would fix the issues the union claims make the train unsafe. But he has since learned the money is part of the existing contract.

Mr Tudehope was asked on Thursday if the money in the budget was for the union’s requested alterations.

“I’ll take that on notice,” he said.

“There are still negotiations to take place in relation to how we reach an agreement with the union in respect of the variety of claims that they are making.”

Mr Tudehope said the new trains were state of the art and had been approved by the Office of the National Rail Safety Regulator.

The union has previously said the safety assessment was conducted by the same company that built the trains, and it had independent assessments that differed in opinion.

If there is no outcome on Friday afternoon, industrial action will begin on Tuesday with a go-slow movement when drivers will not exceed 60 km/h.

On Wednesday, members are indefinitely banned from moving back to the rail operations centre, and will work only from their current depots on Thursday. There will also be an indefinite ban on work relating to Sydney Metro.

On Friday members would refuse to drive foreign-built trains, taking new trains introduced since 2011 out of service.

Mr Claassens said the network would run at about 30 per cent capacity without those trains. It has done that before in recent months when the union took similar action.

“Management’s got a timetable that they can run where they know the trains that they can use and how that will operate,” he said.

“They’ve done it before, they can do it again.”

Mr Claassens said workers had acted in good faith during the long-running negotiations for a enterprise bargaining agreement after the old one expired over a year ago, but their patience was wearing thin.

“To be honest they’re a little bit frustrated with me and other people who were saying to them, ‘let’s give the government the opportunity to come good on this’ … they’ve had plenty of time and yet they keep stalling,” he said.

-AAP