More than 400 surgeries have been cancelled as nurses strike across NSW despite an independent recommendation to accept an interim pay rise and continue negotiations.

The 24-hour stop-work action by nurses and midwives on Tuesday will affect 454 elective surgeries and temporarily close 81 beds, but support for life-saving care is not expected to be impacted.

Health Minister Ryan Park said he was disappointed with the action by the union.

"The independent umpire has said very clearly that this action shouldn't take place," he said.

"People are going to have important surgery cancelled today ... this is going to have an impact on the treatment of chronic conditions."

The government had not made a genuine attempt to negotiate on pay and conditions, NSW Nurses and Midwives general secretary Shaye Candish said.

"The state government could have stopped this industrial action from occurring by coming to the table with an improved offer, but it has chosen to ignore us repeatedly," Ms Candish said on Tuesday.

"Nurses and midwives are outraged by the government's unwillingness to negotiate beyond its insulting three per cent offer, especially since we found the savings to fund the pay rise."

Industrial Relations Commission president Ingmar Taylor had not yet examined the union's argument for pay rises, but recommended an interim agreement and four weeks of "intensive discussions" in a bid to broker a deal.

The NSW Nurses and Midwives Association action started at 7am in the union's second major stop-work action since Labor came to power in March 2023.

The strike is part of a union push for a 15 per cent, one-year pay rise, a demand Premier Chris Minns says is unaffordable.

"If we agree to that, we'll be stretched to breaking point" Mr Minns said on Monday.

"It's not because we don't think that the work they do isn't vital. It is."

Other workers would be lining up for pay rises  if the nurses got the 15 per cent they sought, he said.

All NSW public sector workers, including nurses, have been offered a three-year, 10.5 per cent pay increase factoring in a mandatory rise in superannuation payments.

Opposition Leader Mark Speakman said the government needed to make sure the strike did not compromise patient safety.

"It's also incumbent from the nurses union to co-operate to the same extent," he said.

Public rallies are planned outside parliament house in Sydney and in Tweed Heads and Albury near the Queensland and Victorian borders, two states the union says nurses are moving to because of better pay.