An estimated 100,000 workers are set to go on strike this coming Thursday, despite warnings from the Public Service Minister.

Judith Collins has penned a letter to New Zealanders claiming the planned industrial action is 'unfair' and 'unwarranted'.

PPTA president Chris Abercrombie has responded to Judith Collins's critique of unions being political by saying - of course they are. 

"Well, we're dealing with the Government, so it has to be political. The Government makes the decisions about NCEA, they make the decisions about curriculum, they make decisions about AI marking - they make all these decisions. So it has to be political."

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