The union representing telecommunications workers made redundant by a Telecom subsidiary, Chorus, wants Communications Minister Stephen Joyce to mediate in their dispute.
The Engineering, Printing & Manufacturing Union says significant service backlogs could grow unless issues with the change to the new contractor, Visionstream, are resolved.
EPMU national secretary Andrew Little says just one bout of bad weather could cause big problems, and he wants the Mr Joyce, to intervene before that happens.
Chorus acknowledges there are delays in Northland, but says the situation in Auckland is improving.
It says Visionstream has more than 90% of the workforce it needs.