NSW paramedics are pushing for a 10 per cent or higher pay rise as well as an additional 2000 staff to turn around deteriorating ambulance response times across the state.

Industrial action by paramedics on Monday meant they refused to leave their usual posts to fill gaps at other ambulance stations.

Nurses are also threatening more industrial action later this month after calling for a 4.75 per cent wage increase, better nurse to patient ratios and more maternity staffing.

Thousands of public hospital nurses are voting on whether to strike for up to 24-hours on March 31, after undertaking Industrial action six weeks ago.

Health Services Union NSW Secretary Gerard Hayes says paramedics need a pay rise substantially higher than the 2.5 per cent on offer.

"It could well be higher than 10 per cent," he told reporters.

"Over the last 10-15 years paramedics have been getting 2.5 per cent - now that doesn't barely keep up with CPI."

NSW Opposition leader Chris Minns says the state doesn't want industrial disputes heading into winter.

"The government can't have it both ways," he said.

"You cannot have inflation expected to grow at 3.1 per cent, petrol grow at 30 per cent, rent grow at 12 per cent... while at the same time say to your own public servants, we'll pay you well below what the expected inflation number will be in NSW."

The union also says an additional 2000 paramedics are needed to address steadily declining ambulance response times.

Mr Hayes said more than 84 intensive care paramedics should be rostered on in Sydney every 24-hour period, but NSW Ambulance no longer replaces sick and injured specialised staff leading to gaps in the health system.

According to the union, Western Sydney hospitals were without specialist paramedic coverage on at least 23 occasions between 24 January and 24 February.

"There is no escaping the fact that NSW needs more paramedics and they need proper professional recognition," Mr Hayes said.

In February, paramedics took similar 24-hour action amid claims of worsening working conditions, including staff doing 16-hour shifts without breaks.

NSW Ambulance is meeting with the union at the Industrial Relations Commission on Monday in a bid to resolve the dispute.

NSW Nurses and Midwives Association General Secretary Brett Holmes told AAP money alone would not fix nurses concerns.

He pointed to larger structural problems bogging down the health system in terms of retaining staff and paying them wages commensurate with experience.

The call to walk out comes after thousands of nurses rallied outside NSW parliament in February, and as nurses begin voting on further industrial action at the end of the month.

A new Bureau of Health Information report released last week found a record number of people needing emergency care turned up at NSW public hospitals in the last quarter of 2021, while ambulance call outs also increased, amid the COVID-19 Delta and Omicron waves.