“These guys might be able to help Jim Chalmers see the light on this. It's a terrible policy.”

When asked why the opposition did not raise the controversial $3 million super tax earlier in the election campaign, Hume said the Coalition had been advocating against the policy since it was first announced two years ago.

“This was one of Labor’s first policies [after the last election]. They came out of the gate with this at the beginning of the last term of government, after saying that they weren't going to make any changes to taxes, and after saying they weren't going to make any changes to super,” she said.

“They broke two lies in one go with this policy. We immediately said that, not only would we oppose it, but we would repeal it. We said that we would repeal it in government. Now that's not a small deal.”

The opposition saw the tax as “profoundly unfair”, she added.

“Not only does this tax superannuation after people have committed money that they've already put away on a promise that it would not be taxed at 30 per cent, that it would only be taxed 15 per cent, but it's not indexed,” Hume said.

“We know that it's going to affect younger people, not just older people. It's not just 80,000 people now; in fact, it's going to be hundreds and thousands of people into the future. Young people today who are earning average wages will be affected by this superannuation tax, and moreover, it's also a tax on unrealised capital gains.”

Hume said taxing Australians on a profit they have not made is “disastrous on so many levels”.

“Labor had the opportunity to pass this legislation in the last parliament, but two of the crossbench in the Senate said they had to [make amendments].”

“Labor refused to do it, which I think speaks volumes about what this tax intends to do. It is a retirement tax. There is no doubt about it, and this is going to be following Labor around for a while now.”

When questioned on the possibility of the new ministers changing his mind on the design of the tax earlier in the week, Chalmers said it is “not something that you should anticipate”.

“It’s not something that we’re considering or planning, for all of the reasons I ran through comprehensively a moment ago when you asked me the first time,” Chalmers told Sky News.