The job action — and a planned strike in August by elementary schoolteachers — poses a challenge to the center-left Labour government of Prime Minister Jacinda Ardern, who came to power in October on a campaign platform of fairness and a better deal for ordinary New Zealanders.

New Zealand nurses last walked off the job 30 years ago.

The union representing them said nurses are propping up the public health system — which New Zealanders have access to at no cost — with “huge” amounts of unpaid overtime, with some nurses opting to move to Australia for better pay.

The planned strike would come days after workers for two government departments walked off the job Monday. Elementary schoolteachers also are planning to strike in August for the first time in 24 years, also over pay.

The center-right opposition National Party said Labour had raised expectations too high before the election in September, with government workers expecting big pay increases.

Ardern is on parental leave after giving birth to her first child in June. She will return to work in August.

The acting prime minister, Winston Peters, acknowledged that the unions representing government workers believed they had a more sympathetic ear in the new government after nine years of center-right leadership for the country.

“You go to a bus stop when a bus starts to come by,” Peters said. “It’s not like the previous government, where you’d go to the bus stop and the bus wouldn’t turn up at all.”

But he was adamant that the government had no more money for nurses’ pay beyond the 550 million New Zealand dollars ($377 million) it had already offered, along with an offer to pay for the hiring of 500 more nurses.

“It’s not that we’re not willing,” he said. “We haven’t got the money.”

He urged nurses to reconsider the walkout Thursday, saying the government had taken over a public health system that was “deeply in debt.” Peters promised that larger pay increases would happen, but said they would take time.

In its last offer, the government had proposed that nurses get pay raises of 12.5 to 15.9 percent over 25 months. Many nurses want as much as 20 percent, as well as better working conditions and more opportunities for professional development.

A spokeswoman for the nurses’ union, Cee Payne, said New Zealand’s public hospitals had been severely underfunded for the past decade, with the government not accounting for growing community demand and an aging population.

She said the “extremely high workload” had led to low morale among nurses as well as stress and fatigue, driving some to move to Australia for higher pay.

“I feel for the current government, who are wearing the price of the neglect of the previous government,” Payne said.

But she disputed Peters’ claim that there was no money available, noting that the government had announced Monday the military’s purchase of four Boeing maritime patrol planes.

“Maybe if they only bought three?” she said.

Ninety-three percent of New Zealand’s 27,000 nurses are women, and Payne said that was “definitely” a factor in why their pay had lagged.

Ardern, 37, who became Labour’s leader less than two months before the election, drew global attention with her rise to power and her decision to take parental leave, which was seen as a symbolic victory for working women.

Ardern was asked about the nurses’ pay negotiations when she left Auckland City Hospital, the largest public hospital in New Zealand, with her baby daughter in June. She said her experience giving birth in the public health system had reinforced her belief that the “value in that workforce” needed to be reflected in their compensation.

Four thousand workers from two government departments walked off the job Monday in the first of two such planned job actions. The unions conducting the walkouts, representing workers from the Inland Revenue Department and the Ministry for Business, Innovation and Employment — which includes New Zealand’s immigration agency — said their members’ pay had not kept pace with the cost of living.

Elementary schoolteachers are asking for a 16 percent pay increase over two years to help recruit and retain staff. The government has offered them between 2.2 and 2.6 percent.

This article originally appeared in The New York Times.

Charlotte Graham-McLay © 2018 The New York Times