A political pundit believes a schism is starting to form within Labour when it comes to tax following the resignation of David Parker from the Revenue Minister role.
Prime Minister Chris Hipkins was forced to make another Cabinet reshuffle on Monday after Kiri Allan's arrest and subsequent resignation from her portfolios.
During the reshuffle, it was also revealed Parker would relinquish the Revenue portfolio.
Parker said remaining Revenue Minister would have been "untenable" following the Prime Minister's decision to rule out a wealth and capital gains tax and torch a tax switch idea.
He admitted to being "disappointed" by Hipkins' decision as he had worked "intimately" on the tax-switch proposal.
Bryce Edwards, a political scientist from Victoria University, told AM Early on Thursday the drama surrounding Allan's arrest and subsequent resignation has overshadowed Parker's move.
He told AM Early host Michael O'Keeffe for Parker to resign from the revenue role just 79 days before this year's election was "extraordinary".
"To have a minister resign from their portfolio 11 weeks before an election and at the same time saying he's disappointed with the Government's direction on tax and he's essentially giving a vote of no confidence in his government on one of the biggest policy areas in the election," he said.
"So this is a huge spanner in the works for Labour and it suggests there is dissent within Cabinet, within the caucus on this key issue."
Edwards believes it isn't just Parker who is disappointed with the Prime Minister's decision to rule out a wealth and capital gains tax and ditch a tax switch idea.
Finance Minister Grant Robertson was critical of Hipkins' decision to ditch the tax-switch proposal, saying it had "merit", but he's a "team player" and continues to believe in the Labour Party.
Edwards told AM Early he believes Parker is speaking for more than just himself when it comes to tax.
"When things start to fall apart, dissent becomes more obvious and you start getting more leaks, you start getting disunity and there's no doubt there are a lot more people in Labour in the rank in file, in caucus, in Cabinet that are also disappointed," he said.
"So there really is a hope for a more progressive direction for Labour than just David Parker."
He told AM Early the issue of tax is dividing the party and could affect Labour leading up to the election.
"Tax is the big issue at the moment and for Labour to essentially go along with the National Party consensus on tax, I think is alarming for a lot of people on the left, really, so there is a schism that's opening up here. We're yet to see whether it will open further," he said.
Edwards wondered if this was the final straw for Parker that could see him bow out of politics after first joining in 2002.
"There are people on the left that have been very demoralised by Chris Hipkins's decision to rule out a wealth tax and maybe this is just the case of David Parker heading towards the door," he said.
"It has been rumoured for a long time that David Parker wants to retire and maybe he's just had enough and he's finally got frustrated, so we're starting to see some of that frustration come out.
"But of course, there could be a time when Chris Hipkins actually is no longer the leader and maybe that will come sooner rather than later and David Parker might be well-positioned to even be that candidate for being the leader of the Labour Party."
Watch the full interview with Bryce Edwards in the video above.