The signatures include fewer than 10 Liberal MPs out of a party room of 85, signalling their difficulty in mounting a serious challenge to Mr Turnbull. Another 10 members or more are Nationals. “This is people talking a big game – a small group of people making trouble,” said one of the group’s opponents. Western Australian Liberal MP Ian Goodenough played down the demand for policy change in the statement, saying he had only signed up to a "social group" and that it was "not designed" to be a challenge to Mr Turnbull. "It's looking at options for cost-effective electricity and not ruling anything out," Mr Goodenough told Fairfax Media. Take my advice, mate: Malcolm Turnbull and local Norm Clarke at a community lunch in Brisbane. Credit:AAP

In a strategy that ensured media attention, the backbench claims were aired by Mr Abbott’s former chief of staff, Peta Credlin, on Sky News on Monday night before fuelling a full day of debate among politicians and the media on Tuesday. The group includes prominent MPs who have fallen out with Mr Turnbull including Mr Abbott, former defence minister Kevin Andrews, former workplace minister Eric Abetz and former Nationals leader Barnaby Joyce. Two other members are western Sydney Liberal MP Craig Kelly and outspoken Queensland Nationals MP George Christensen. Others have denied public reports claiming they were members. Western Australian Liberal MP Andrew Hastie said he had not signed the letter. Mr Turnbull rejected the idea of amending the National Energy Guarantee in light of the renewed push from the backbench, insisting the issue had been settled last year. “Our National Energy Guarantee has been endorsed by the whole party room, the whole Coalition party room,” he said.

“It’s got strong support from industry, it’s got strong support from state jurisdictions, it now has the support of the South Australian government following the change in government. “It’s vitally important that it is adopted because what we need is a technology agnostic energy policy that encourages investment and that’s precisely what the National Energy Guarantee will do.” The NEG is contentious within the Coalition because it seeks to cut greenhouse gas emissions by 26 to 28 per cent by 2030 through the use of regulations imposed on energy retailers. Loading But the policy was formally cleared by the Coalition party room late last year despite criticism from Mr Abbott and others, suggesting they cannot get the numbers in the party room to impose their will.

Energy Minister Josh Frydenberg will meet state and territory counterparts on April 20 to get approval for the high-level design of the NEG, after a meeting of officials on April 11 to clear some of the ground. Labor and Liberal state governments appear close to an agreement but ACT Climate Change Minister Shane Rattenbury, a Greens MP, is pushing for changes to favour renewable energy. Mr Rattenbury made no threat on Monday to veto the deal but warned the Turnbull government against giving in to the ginger group. “Rather than be held hostage by the dinosaurs on the federal Liberal backbench, I’d encourage Josh Frydenberg to stay the course and deliver a clean, green, renewable energy policy that will serve all Australians, both now and into the future,” he said. The NEG is not due to go back to the Coalition party room for several months. Mr Turnbull is expected to hold a meeting with state and territory leaders in August to agree on the policy.