Engineers upgrading the Waikato section of the power grid are taking industrial action, claiming Australian workers on the same project are getting paid up to three times more.
The Engineering, Printing and Manufacturing Union says it has tried to negotiate better pay rates, but the discussions have stalled.
Union spokesperson Joe Gallagher says Australian company UGL, which is doing the upgrade work, brings workers over and pays them significantly more than locals.
Mr Gallagher says the company gives the Australians travel expenses and better overtime rates.
The industrial action will include 40 workers refusing to do more than a 40-hour week and will begin later in October, he says.
No one from UGL has been available for comment.
