Health New Zealand has ordered an immediate hiring freeze on all non-frontline roles.
The directive was laid out in an email sent to all staff on Thursday and leaked to RNZ.
In the email, chief executive Margie Apa told staff the recruitment freeze applied to all hospital roles that did not deal directly with patients and all public health jobs that did not deal directly with the community.
The only exception was for those people who were offered a verbal offer or a contract before midday on Thursday.
Apa said the measures were aimed at reducing overspending.
Health NZ had made "significant advances" in recruitment in recent months.
However, "this comes at a cost where we find ourselves spending over our current year budget", she said in the email.
That was especially true in hospital and specialist services where more nurses had been hired, she said.
The freeze would be in place until at least when the budgets were set for the next financial year.
"These new measures will not impact frontline services," Apa wrote.
"Staff and patient safety and clinical delivery remain our priorities and will be considered when making decisions on which roles to progress."
All candidates going through the recruitment process, who had not been issued a contract or verbal offer, would be told that recruitment was "pausing at this time", Apa said.
"I know that these changes will raise some questions, perhaps more so for those in areas where recruitment is being paused," she said.
"Please talk to your manager about how your teams will manage any change in your area.
"Thanks for your support in this ongoing effort to keep us within budget while still maintaining vital frontline services."
Earlier this year, the organisation ordered a ban on double shifts in a bid to cut its operating costs.
It also asked managers to review unfilled roles in their teams and "consider permanent removal of these as part of the budget processes".
However, Apa said at the time it was not a hiring freeze.
"Particularly where if you've had roles that have been vacant for [a number of months] and you've been able to function as a service, I think it's reasonable for leaders to check whether they need that role or whether they need the job carried out in the same way that they might've assumed when they thought they needed that role."
She said staff were being reminded of "some of the things we need to do to ensure we live within our means".
"We need to make sure we're as efficient as we can be in our day-to-day operational practices."
Health NZ also introduced changes to recruitment back in April, saying no new hire was to start on in a non-clinical role before 1 July without top-level approval, and only at existing rates.
Jobs that will be affected
The directive from Apa did not cover the extent of the cuts.
"We think it's worse than as described", Association of Salaried Medical Specialists executive director Sarah Dalton said.
Clinical and frontline roles like radiologists and booking clerks were being affected, Dalton told Morning Report.
"I had our members contacting us over the last few weeks where they have been not able to recruit paediatricians, cardiologists, obstetricians, gynaecologists, cancer specialists, public health physicians. This is widespread."
She said the books would never balance because there was already a shortage of doctors, nurses and allied health workers.
"We have staff who are being asked to work extra hours and expected to do it without being paid for it.
"We have doctors working ridiculous hours to try and hold services together ... it is not a good situation."
"This is effectively a sinking lid on recruitment into core health services and it's a real problem and it's going to create real risk."
She questioned the government's priorities between potholes and hospitals.
"It seems wrong."
Health NZ issues statement
A statement from Apa on Friday morning echoed the leaked email.
It said Health NZ had found itself affected by the same general cost pressures felt in the wider economy and it was "introducing some further controls" to help manage the current year's budget overspend, without impacting frontline service.
"Staff and patient safety and clinical delivery remain our priorities," it continued.
"We have brought in an organisation-wide pause on all current and new recruitment of hospital roles that are not patient facing and Public Health roles that are not community facing.
"There are similar restrictions on all enabling services, such as People and Communications and Finance.
"We are also changing the approval process for recruitment within Hospital and Specialist Services.
"We are removing the recent national approval process and will replace it with a regional process, to assess, prioritise and approve the recruitment of roles in hospitals.
"The process for approval of frontline public health roles will continue.
These new processes will help us continue to address the budget overspend, but in a way that is closely informed by local clinical priorities.
"No frontline budgets are being cut."
Health NZ must stick to its budget - Minister of Health
In a statement to RNZ, Minister of Health Dr Shane Reti said the government had "invested significantly" in health in Budget 2024 and Health NZ "must ensure it lives within the funding provided".
"I'm aware Health NZ is putting in place additional measures to ensure it can manage within its appropriation for both this financial year and next," he added.
"I've been assured it will manage this in way that will not impact clinical delivery and patient safety."