Sunday night court order blocks unions from striking after Sydney ...

Unions have been blocked from carrying out further train strikes after pay talks with the NSW government broke down following weeks of negotiations.

The talks collapsed yesterday as Premier Chris Minns said he couldn't "say yes" to the rail unions' demands while denying claims from nurses and other sectors.

Fearing disruptive strikes in the lead-up to Christmas, Transport for NSW-operated Sydney Trains took the Rail Tram and Bus Union and others to court to try to block industrial action.

In a hastily organised hearing last night, the Federal Court agreed to issue an interim restraining order doing exactly that.

The unions were ordered not to carry out industrial action and to let their members know that any such plans were not authorised.

Minns on Sunday afternoon said the government's best efforts to do a deal had failed.

"I'm disappointed and I'm very sorry about it, but unfortunately that's where we are," he said, in a statement.

"At the end of the day I can't say yes to the rail unions whilst at the same time say no to the nurses union and other unions reaching reasonable settlements over the course of 2024."

The RTBU gave the government both barrels in response, calling the specific legal route taken an "underhanded tactic" echoing methods used by the former Liberal state government.

"Shockingly, it appears to have the full backing of the NSW Labor Government – a move that is appalling, disgraceful, and utterly unforgivable from a party claiming to support workers," the union said.

"These actions come as a surprise, given that negotiations with the Premier's Department and Treasury had been progressing reasonably well.

"For the Premier to publicly declare it's 'all too hard' and announce plans to take unions to court marks a dark and shameful day for the NSW Labor Party – a direct attack on all workers in this state.

After the court order, it said plans were already underway to run a new member ballot allowing further strike action.

Before taking the legal route, the premier had asked the rail unions to pull any plans to strike this week.

Last Monday, Minns said Sydney could see industrial action if a deal between the Government and the Rail, Tram and Bus Union wasn't reached by today.

The union's interim agreement not to launch industrial action lasts until today.