Environment and Energy Minister, Josh Frydenberg, told Fairfax Media the government's intention was to stick with its policy and contrast it with Labor's commitment to a more ambitious target for 2030 that would be a "reckless hit on family and business electricity bills".

In a direct repudiation of Mr Abbott's assertion that the existing policy would increase prices, reduce reliability and threaten heavy industries, Mr Frydenberg said: "The government has no plans to change the 2020 RET which was settled just 18 months ago providing investor certainty."

Mr Abbott delivered a scathing critique of the government on Saturday, just as Mr Turnbull began discussions with senior colleagues on who would fill the key health portfolio after Sussan Ley's forced resignation over her travel claims.

Mr Abbott would not have been considered for the vacancy, but his comments in a weekend opinion piece in The Australian are set to end any hope he had of a return to the cabinet under Mr Turnbull.

Mr Turnbull is committed to a minimalist reshuffle, but is still weighing up the case for assigning cabinet secretary and acting health minister Senator Arthur Sinodinos to the role.

While Senator Sinodinos is regarded as a "safe pair of hands", his appointment would mean the new health minister would not be in the lower house to confront Labor on what Mr Turnbull concedes is one of the most contested policy areas.

Mr Turnbull is weighing up whether this drawback would be outweighed by the complications of switching one of the government's heavy hitters in the lower house to health and having a gap to fill in another key portfolio as a consequence.

One minimal change would be to give Industry Minister Greg Hunt the health role and assign his portfolio for Senator Sinodinos, though there was no sense on Sunday that this was actively being canvassed.

Having indicated a desire to return to the front bench late last year, Mr Abbott appears to have concluded that Mr Turnbull has no intention of accommodating him, so he will exercise his right to speak freely from the backbench.

In a piece ostensibly about the challenges of the Trump presidency, Mr Abbott lamented that Mr Turnbull had abandoned the tax reform and federation reform white papers Mr Abbott commissioned and said the government was in "a worse position" than it was 18 months ago (when he was leader) to embark on a major new round of economic reform.

He said the government's first move this year should be to introduce legislation to protect existing renewable generation "but to remove all further mandatory use requirements".

Mr Abbott said the existing policy would almost double renewable energy supplies in the next four years, increasing power costs and reducing reliability. "If it goes ahead, it will be the death knell for the heavy industries of Whyalla and Port Pirie in South Australia and almost certainly will destroy the aluminium industry everywhere," he wrote.

"Ending any further mandatory increase in the use of renewables will mean a huge fight in the Senate, but at least the government will be on the side of lower power prices and more jobs, while Labor will be stuck on a dangerous limb with the Greens."

Aside from inviting such a fight in the Senate, government figures say such a move would be disastrous, breaking an agreement with Labor on the 2020 RET, giving industry more uncertainty and inviting an electoral backlash.

Coalition MPs were not expecting a major reshuffle on Sunday, saying any major reshuffle would not be contemplated before mid-year.

"Not this time," one said. "Ultimately, there will be, but I don't think there is any appetite for a larger reshuffle at this stage.

"But obviously it is an important portfolio, so there is a need to put in someone very strong."

"Nothing is certain and there are still calls being made," another said. "But there hasn't been anything to indicate that there will be a wider reshuffle, at this stage."

With Amy Remeikis

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