ACC Minister Judith Collins is describing a call for her to stand down from the role as "silly nonsense".
Labour's ACC spokesperson Andrew Little said the resignation of chief executive Ralph Stewart and board chair John Judge were evidence of "utter chaos" at the corporation.
He called for Prime Minister John Key to "relieve" Collins of her portfolio, but Collins said Little was being "desperate".
"The other day I heard him [Little] calling for the chair to go, well the chair's gone. I've heard him calling for the CEO to go, well he's gone. He called for my colleague Dr Nick Smith to resign, he resigned. It actually has to stop, this silly nonsense from Mr Little."
Collins said she would not be apologising for anything she has said regarding privacy breaches at the corporation.
The departures come as ACC remains under investigation for privacy breaches which have seen clients' confidential details mistakenly emailed to wrong recipients.
In another twist, Labour says ACC has shelled out a large sum of money to a PR company to help them handle this saga.
"That is just unforgiveable from an organisation that is set up to look after people who are injured," Little said.
Little said National has "managed to create a shambles out of New Zealand's world-class insurance agency".
He said Collins is presiding over "a chaos of resignations".
"We have seen two resignations in two days in what is a desperate scramble by Judith Collins to try and regain credibility," Little said.
"This is a political stitch-up and a last-ditch attempt to regain control of a situation which has escalated because Judith Collins has had her eye off the ball."
Stewart 'deeply frustrated'
Stewart's announcement came in a statement to staff on the ACC website, a day after Collins announced that Judge will stand down at the end of the month.
Board members John McCliskie and Rod Campbell will also be replaced.
"The events of recent days and the departure of our chairman and a number of our directors, has brought me to the point where I have decided to step down as CEO. This has been an incredibly hard decision to take and one that I have considered very carefully," he said.
Stewart has been at ACC for six months. He was formerly the head of AXA New Zealand for seven years, prior to taking up the post.
"In the relatively short time I have been here I have quickly come to respect ACC's people, purpose and commitment to supporting the New Zealand way of life. I am deeply frustrated that the benefits of the scheme and the great work we do has been overshadowed by recent events," he said.
"You have made great strides on our plan to transform ACC. I'm going to ask you all to keep faith with the plan, which I know is supported by the Minister and has been supported by the Board for many years." Stewart said.
"Please don't be distracted by the current events, our key ambition is to ensure that ACC is strong and capable for the future generations we have talked about so often. I will keep you all informed about developments and the appointment of a new Chief Executive."
'Rebuilding public trust and confidence'
Collins announced yesterday that Judge will be standing down at the end of the month and replaced by former Commerce Commission chair Paula Rebstock until a new chair is appointed.
Collins' statement said Judge's impending appointment as chairman of the ANZ National Bank, from June 23, is the reason for his stepping aside, but cited a need for the corporation to "refocus on rebuilding public trust and confidence."
Asked if she had asked Judge to step down, Collins said: "It is a matter we have been discussing for some time and Mr Judge agreed with me it would be appropriate given his new role and to bring in a new culture to ACC."
Labour claims Judge was rolled.
Judge's position has been under a cloud since the police declined to lay charges against an ACC claimant, Bronwyn Pullar, relating to a leak of private information by the corporation to her, which she allegedly threatened to publish. Judge had backed Stewart's decision to take the issue to the police.
The scandal brought about the resignation of ACC Minister Nick Smith.
Investigations into ACC by the Auditor-General and the Privacy Commissioner are due back in the next few months.
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