Workers at Māori Television will strike for 24 hours next week.
Union members at Māori TV are protesting against what they claim is unfair and discriminatory treatment.
E tū said 27 members would be going on strike after months of delays by Māori TV in addressing members' concerns.
E tū Union industry coordinator Joe Gallagher also claimed the bargaining process was undermined as Māori TV told them they had no money but gave non-union members a bonus and a wage adjustment.
"We think they've undermined the bargaining process by telling us they have no money while giving bonuses and a pay rise to non-union workers."
Mr Gallagher said it was a sign that Māori TV did not live by the values it promoted.
"The direction and behaviour of the management at [Māori TV] is seriously lacking for a company and organisation which promotes the values of tikanga."
Māori TV chief executive Keith Ikin said he was disappointed to learn of strike action through the media.
He was calling on the E tū Union to ratify and bring to a close the prolonged bargaining process in the interest of its staff.
Mr Ikin said the offer of a base pay rise and a payment based on individual performance made during recent mediation and talks was consistent across the organisation.
"We believe that Māori Television has been proactive in engaging with the union, and the offer put forward at recent talks is both fair and reasonable and supports the organisation's performance-based remuneration approach."
A contingency plan has been put in place to ensure viewers were not affected by the strike action, Mr Ikin said.
"We remain committed to progressing the deal and reaching an agreement in the interest of providing certainty for the 27 affected Māori Television staff in the union collective."