Mr Bowen was quick to rule out taking the policy to the next election when Fairfax Media first revealed sections of the Left of the ALP were determined to put it on the agenda to counter the populist appeal of One Nation.

Crucially, it has gained the support of Mr Bowen's predecessor, former treasurer Wayne Swan, an influential member of his own Right faction.

Despite Mr Bowen's resistance, the idea is not yet dead, buried or cremated.

The first meeting of Labor's national policy forum, which sat on Friday at Trades Hall in Sydney, has progressed the Buffett rule as a "priority issue" for discussion.

Some view this as the next step towards the tax policy being debated on the floor of Labor's next national conference, or forcing the Shorten leadership team to offer a compromise policy in the economic inequality space.

A senior Labor figure who has worked to progress debate said: "Chris Bowen thought he could kill this thing dead in one day but that has not happened. Bowen is influential but it is conference that decides what is Labor policy."

Mr Bowen has been emphatic that a Buffett rule would not be part of the policy mix Labor presents at the next election, describing it as little more than an "idea or concept" because no progressive party anywhere in the world has made it law.

He told the Guardian on Tuesday that the Buffett rule was one of a number of "very blunt instruments" that do not fit with the need to balance economic growth with policies that address economic inequality.

Under Opposition Leader Bill Shorten, Labor has kept its focus on negative gearing and capital gains tax policies it took to the last election.

The Buffett rule is named after American tycoon Warren Buffett, who said it was wrong that his secretary paid a higher percentage of income tax than him simply because he could afford better accounting advice.

It would require people earning more than $300,000 a year, for example, to pay no less than 35 per cent of their taxable income as a way to discourage aggressive tax planning and the pursuit of tax loopholes.

In 2015, Tax Office figures showed 77 Australians who earned more than $1 million paid no income tax due to aggressive tax minimisation.

The Corporate Tax Association, which represents some of the biggest business taxpayers, has dismissed the Buffett rule as "class warfare".

The reform idea will be discussed at the next meeting of Labor's national policy forum, a body that is made up of current parliamentarians, rank-and-file members and union representatives.

Mr Swan put more focus on the Buffett rule during a recent speech to the national conference of the Australian Workers' Union, warning that inequality in many countries is "back to 19th century levels".