The Maori King has taken the extraordinary step of sacking a top Tainui figure over a critical report she wrote about the tribe's finances.

King Tuheitia yesterday removed Tania Martin, an elected official, as the chairwoman of Waikato-Tainui's parliament Te Kauhanganui, which represents the tribe's 66 marae.

Ms Martin, who represents Hiiona Marae, was dismissed after writing a report to tribal members that criticised spending by Tainui's executive board, Te Arataura. She also criticised board chairman Tuku Morgan.

King Tuheitia said Ms Martin's report was based on inaccurate figures and she had issued it without giving board members a chance to respond.

"She is well aware of the damaging errors in her report," he said.

"She has been taken through them several times. She has told my [representative] that she has made a major mistake."

In a detailed statement, King Tuheitia said he had asked Hiiona Marae to remove her, effectively dismissing her from the parliament. But the marae rejected the request.

The King dismissed her in his capacity as paramount chief.

"They declined to do so on the grounds that this matter should be handled within the disputes process of Te Kauhanganui. This is not possible because Mrs Martin's actions have rendered Te Kauhanganui dysfunctional," King Tuheitia said.

"She has agreed several times to issue an apology to members of Te Arataura, but has not delivered on those agreements.

"She has committed to meet with Te Arataura and accept offers of mediation of her dispute, and has repeatedly failed to meet those commitments."

In her report, Ms Martin put the board's costs at $1,703,000. The king says the true figure is $656,000.

King Tuheitia said Ms Martin was supposed to meet him last Thursday, but she postponed the meeting as she was receiving medical treatment.

He found out she was being interviewed by a current affairs show.

Waikato-Tainui marae held emergency meetings last night, and some are seeking legal advice on the matter.

The king's Te Arataura representative Greg Miller has been appointed as interim chairman until the parliament meets in February.

The removal is a further sign the king is becoming more active in tribal politics.

Previously, the tribe has said he should stay above day-to-day matters.

Te Arataura chairman Tuku Morgan said the king had to intervene.

"There's only one boss in Waikato-Tainui," he said

Ms Martin could not be contacted last night.