Junior doctors have rejected a call by their employers to withdraw planned strike action next week.
The planned strike comes as dates have finally been agreed for urgent facilitation in the row with district health boards.
On Wednesday afternoon, DHBs called on the resident medical officers to withdraw a five-day strike beginning early next Monday.
They said facilitation by the Employment Relations Authority would take place from 9 to14 May, with written submissions due from both sides on 3 May.
The DHBs urged the doctors to reconsider, saying there was nothing to be gained by another strike.
They said that the next strike, being longer than the four earlier two-day strikes, would have more impact on hospitals.
But the doctors' union, the Resident Doctors Association, rejected that call, saying that the strike at all DHBs except Canterbury would proceed as planned.
David Munro of the Resident Doctors Association said it was too late.
"It's very much eleventh hour. The [strike] notices are in place, the contingency planning is in place. And as we have said on many previous occasions, it's a settlement that will stop the ongoing strike action," Mr Munro said.
The DHBs' spokesperson, Peter Bramley, said it was disappointing.
"We're quite surprised that the Resident Doctors Association is still insisting that the strike go ahead.
"They requested urgent facilitation, it's been granted, dates have been set and from a DHB perspective we can't see why there's a reason to strike and unfortunately, striking is simply going to create further disruption to patient services."
The doctors' union and district health boards have long been at an impasse in their row over the doctors' employment deal which expired in late February.
Mr Munro has previously said the issue was not about pay but about changes the DHBs wanted to make to the now-expired employment agreement.
Canterbury has been omitted from the strike because the hospital is still under pressure from the mosque shootings.