Thousands of junior doctors are to stop work for 48 hours in a dispute over hours, which could cause major disruption to the public health system.
A notice of strike action has been issued after mediation talks failed to reach settlement on Monday afternoon.
Junior doctors plan to walk off the job for 48 hours from 7am on October 18.
A lack of money and patients with increasingly complex problems are forcing resident doctors to forgo breaks and rest, according to their union, the NZ Resident Doctors Association (NZRDA).
NZRDA national secretary Dr Deborah Powell says the union was left with "no choice" after 10 months of bargaining.
"It's extremely disappointing it has come to this," she says.
"We see no other way to secure safer rosters for our nation's doctors and the patients we care for."
A recent survey of NZRDA's 3600 members found 275 of them had fallen asleep while driving home after shifts that can be as long as 16 hours, 12 days in a row.
Almost a third of the doctors surveyed said they'd made a mistake affecting a patient because they were tired. Dr Powell told Paul Henry on Thursday it would only take another 140 doctors to fix the problem, but the district health boards just don't have the money.
Ironically, she says it wouldn't cost much more to just hire additional doctors because DHBs wouldn't have to pay the existing crew as much, since they'll be doing fewer hours.
So far, only 13 of the 150 nationwide rosters meet the NZRDA's requirements.
All DHBs will be affected by the walkout.