The National Party’s deputy leader has claimed Labour is “cooking up” a new capital gains tax and has demanded they open up about it.

Speaking at the party’s Northern Region Conference this morning, Nicola Willis said the basis of her claim was from being told new tax ideas were already being discussed at Cabinet.

She wants the Government to “come clean with New Zealanders about it”.

“Make no mistake, Labour have always wanted a capital gains tax, they still want one and they are more determined than ever to impose one,” she said at the conference.

Nicola Willis said she'd been told new tax ideas were already being discussed at Cabinet. Photo / Greg Bowker

“The only thing they haven’t finalised yet is its new name and how they’ll spin it. The Prime Minister must rule it out - that he won’t tell you everything you need to know.”

This comes after a two-year investigation by Inland Revenue found New Zealand’s ultra-rich pay tax at less than half the rate of the average person.

Revenue Minister David Parker said earlier this week the report’s findings were “ground-breaking” but wouldn’t say how Government might respond.

“What, if anything, do we do about that [disparity] here in New Zealand? We’re not providing the answers today. That is for the future.”

Willis suggested the Prime Minister has always had an affection for a capital gains tax and would happily introduce it again.

She pointed to a tweet from Hipkins that she said read, “Husband and wife with rental property approached me today to say they like capital gains tax, they think it’s fairer, me too”.

Nicola Willis said Chris Hipkins had previously flirted on social media with the concept of introducing a CGT. Photo / Brett Phibbs

Willis also said Hipkins had held Finance Minister Grant Robertson’s plans for a Jobs Tax-funded income insurance scheme.

“The work continues at pace, with ads going out just this week for two new policy advisors to join the Jobs Tax team.

“This is the same Chris Hipkins who empowered David Parker as his Minister for Revenue to let rip with his big-tax fantasies, the same David Parker who last year came up with the KiwiSaver tax, and who wears his hatred of wealth so proudly on his sleeve.

“New Zealanders deserve to know what’s been discussed and why the Government is being so secretive about their plans.”

She said the Labour Government would be taking advantage of the hard-won gains of every Kiwi who’d built a business, or invested savings for retirement.

“Labour has always resented success.”

She believed the concept would become a repeat of Three Waters - with the Government imposing mandatory co-governance.

“They’ll call it something new, they’ll make new excuses for it... but their long-standing desire to launch an envy-driven tax grab has not changed.

“Everyday Kiwis will pay the price.

“New Zealanders can’t trust Labour on tax.”

She said National’s plans were clear.

“We say no to a capital gains tax. We say no to an inheritance tax. We say no to a wealth tax. We say yes to reducing tax paid by working people. If we are elected this year that’s exactly what we will deliver.”

Labour has been approached for comment on Willis’ claims.

RNZ reported earlier this week that one of New Zealand’s wealthiest people had no issue with a capital gains tax.

The unnamed rich-lister had made his fortune on untaxed capital gains but supported taxing those gains, saying it was only fair to bring New Zealand into line with other countries.

However, he said a more broad-brush approach - like a capital gains tax on all properties beyond the family home - would do more for the Government’s revenue.