The NSW treasurer says he's disappointed the state's paramedics have gone on strike but "complex entitlement issues" curtailed any last-minute truce.
Thursday's strike means NSW paramedics will go to urgent, life-threatening jobs but won't attend less serious incidents like a broken arm.
The strike has not been approved by the NSW Industrial Relations Commission, meaning the Health Services Union could potentially face fines.
The HSU said it did not take the move lightly but supported the strike because the state's paramedics were underpaid and disrespected.
Treasurer Dominic Perrottet on Thursday said he'd worked through several issues with the HSU on Wednesday, many without significant progress.
He said his government had not yet settled on a wage policy for public servants, which will be revealed in the June 22 NSW budget.
The government sought to freeze public sector wage rises at the height of the COVID-19 pandemic, instead allocating funds to stimulus packages.
"I'm disappointed they're going on strike today," he told 2GB radio.
"There are issues there that aren't going to be resolved overnight."
HSU secretary Gerard Hayes told reporters on Wednesday the union would not "walk away" from the strike or a pay rise for paramedics.
Paramedics are upset they've effectively been given a pay cut despite working on the front line during the COVID-19 pandemic.
This year's proposed 1.5 per cent pay offer was less than inflation, which NSW Treasury forecasts at 2.2 per cent for the coming year.
Premier Gladys Berejiklian said on Wednesday that her government wanted to help frontline workers and urged everybody to "wait for the budget".
Australian Associated Press