The Nurses Organisation has called a nationwide strike in December over its pay dispute with Health NZ.

Te Whatu Ora members have voted to strike on December 3 between 11am and 7pm, and embark on rolling strikes in districts across the country in the following two weeks.

Nurses were feeling undervalued and were worried patient safety was being put at risk, Nurses Organisation chief executive Paul Goulter said.

"Nurses all around New Zealand working in the public hospitals are tired, they're frustrated, they keep being promised things, they keep being told 'we value your work', but in fact when it comes down to it there's no evidence their work's being valued."

Health NZ was suggesting pay rises far below what nurses deserved, he said.

It had capped any increase at 1 percent of total employee costs - which would mean 0.5 percent in the first year because it would not come into effect until April 2025 - and up to 1 percent in the second year.

The Nurses Organisation had told members that meant they would be offered a wage increase well below the rate of inflation - effectively a pay cut.

Nurses needed pay rises that reflected at least the cost of living, and recognised their skills and knowledge, the union - which represents about 56,000 nurses and health workers - said.

Nurses were also alarmed at plans to pause a digital staffing system used in hospitals to indicate how many full-time staff were needed on duty at any given time, the union said. That would leave few safeguards on staffing levels and result in fewer nurses, midwives, health care assistants and kaimahi hauora on duty.

The union said that would put patient and whānau safety and wellbeing at risk, and patients would pay the price for hospitals that were continuously under-staffed and under-resourced.

Te Whatu Ora Northern regional deputy chief executive Mark Shepherd said it was "disapppointing" the union had ratcheted up industrial action with negotiations having barely begun.

"Health NZ values the enormous contribution of our nursing workforce and thanks them for their critical work, but we are disappointed that strike action is being taken so early in the bargaining process," he said in a statement.

The agency was committed to reaching a settlement with the Nurses Organisation and averting strike action. However, any settlement had to "reflect the ongoing reset of Health NZ", including its work to "get back to budget and complete the restructuring underway", Shepherd said.

Contingency planning was underway in the event the strike went go ahead.

"I want to reassure the public that our hospitals will remain open during the strike action and doctors and other health professionals will still be available to ensure the continued availability of health services for those who need them.

"We are working with NZNO to ensure agreement to the life preserving services which need to be provided during any strike action.

Information will be provided in advance to patients whose health care may be impacted in the lead up to or during the strike, and the public will also be kept informed of how the industrial action may affect other services.

The strike notice related to only the December 3 strike, but the union has signalled its intention to call rolling strikes later.

-RNZ.