Former prime minister Paul Keating says the suggestion that increasing the employer super contribution from 9.5 to 12 per cent would stifle wages is "the great lie".

Key points: Paul Keating says some people in the Liberal Party are "super deniers"

Paul Keating says some people in the Liberal Party are "super deniers" He says Labor lost the last election because it "failed to understand the middle-class economy"

He says Labor lost the last election because it "failed to understand the middle-class economy" Mr Keating likens US Secretary of State Mike Pompeo as "Rodney Rude"

"It's demonstrably false because nobody since 2014 has had any increase in super, there's been no 2.5 per cent, yet wages have not increased at all," he told 7.30.

A clutch of backbench Liberal MPs have been defying the Morrison Government's official line on superannuation in recent weeks, arguing against a scheduled and already-legislated increase in the employer contribution to 12 per cent.

One newly elected Liberal, Andrew Bragg, went further, saying super should be made optional for low-income earners to give them more flexibility in their finances.

"It's like climate deniers. We've got a bunch of people in the Liberal Party who have always hated superannuation ... they are super deniers," Mr Keating said.

"Someone said yesterday, pithily, they are like anti-vaxxers, they are against vaccine, you know?

"The Parliament is currently legislated to 2.5 per cent extra super from 2021 to 2025. That's 2.5 per cent of income, whether you take it as savings or super or cash, it's still 2.5 per cent of income.

"If this is refused, essentially what a Liberal Government would be doing is pilfering, stealing, robbing the workforce of 2.5 per cent of income."

Why Labor lost

Mr Keating said the Labor Party lost the last federal election because "it failed to understand the middle-class economy that Bob Hawke and I created for Australia".

"So much of Labor Party's policies were devoted to the bottom end of the workforce and the community, paid for by cuts in tax expenditures," he said.

"If the cuts in tax expenditures had of been employed in reducing tax rates, then it would have been a big tax reform and I believe a much more successful outcome.

"But instead of that, the Labor Party was actually increasing the top rate of tax from 45 to 47 per cent which, of course, you know, in public I opposed."

Mr Keating said the "top marginal rate in Australia shouldn't be a jot over 39 per cent".

Australia should have 'no bar' of US missiles

Australia should reject any push to station United States intermediate-range missiles in the country's north, Mr Keating said.

US defence secretary Mark Esper sparked intense speculation about the possibility of the weapons being deployed in Darwin when he said would like to see them stationed in the Asia-Pacific, and did not rule out Australia when questioned by journalists.

Prime Minister Scott Morrison hosed down the prospect on Monday, saying the US had not asked and it was not being considered.

"We should have no bar, no bar, of having American intermediate-range missiles stationed in this country directed towards the Chinese," Mr Keating said.

The former Labor prime minister went on to describe US Secretary of State Mike Pompeo, who was also on the visiting delegation, as "Rodney Rude".

Mr Keating was referencing a weekend comment from Mr Pompeo, who, when asked if Australia should prioritise its economic relationship with China or its national security priorities, said "you can sell your soul for a pile of soybeans or you can protect your people".

"The only thing to know about American secretaries of state is, under Trump, they don't last long," Mr Keating said.