Moderate Liberals have warned Opposition Leader Sussan Ley she will lose her authority if she bends the knee to the Nationals over net zero, as Prime Minister Anthony Albanese predicts the Coalition will again implode on the issue of climate change.

The party’s shift towards dumping the net zero target gained further momentum on Tuesday when Ley’s deputy Ted O’Brien refused to back the 2050 goal opposed by leading conservatives. Nationals renegade Barnaby Joyce claimed partial credit for leading the argument against the pledge.

Ley told MPs on Tuesday that a special Liberal-only party room meeting in the next fortnight would help finalise the climate policy before the final parliamentary sitting week of the year starts on November 24, during which the Liberals and Nationals would try their best to harmonise their policies.

Earlier, Moderates came out in force fearing Ley and her office had made up their minds to follow the Nationals to get rid of any mention of “net zero” in the opposition’s energy policy. Ley’s camp insisted to Moderates that no such call had been made, but O’Brien’s equivocation was a sign of where the debate was headed as Ley preserves her leadership.

The Nationals ditched support for net zero emissions over the weekend, instead committing to reducing Australia’s greenhouse gas output in line with a global average, putting pressure on Ley to follow suit.

Frontbencher Tim Wilson warned Ley’s “moral authority” was on the line, calling on Ley to show leadership and arguing the two parties could still land a united position.

“The Liberal Party is not National Party-lite. We will make our own decisions about our own policy, and we will stand up for what we believe in,” Wilson told Sky News.

Referring to Ley’s decision to stand up to the Nationals before the parties briefly split earlier this year, he said Ley had “stood her ground because she knows that once she loses moral authority, you can’t get it back”.

MPs had expected to be given a clear timeline on finalising the Liberal energy policy, but left a joint party room meeting disappointed with the lack of detail on what was being developed by energy spokesman Dan Tehan.

Speaking to his own MPs, Albanese sunk the boot into the Coalition: “Those opposite have torn themselves apart before and are doing it again”, he said, arguing that regardless of scepticism over climate change, investing in renewables and storage was sensible economics.

On Monday, Albanese refrained from politicking over the Coalition’s chaos but on Tuesday, he assailed the opposition in question time.

Right-wingers believe they are winning the argument internally against the Moderates, who have threatened to push for a split from the Nationals, and who privately admit backing a net zero aspiration is probably unachievable but insist it is important to retain to keep voters onside.

Opposition housing spokesman Andrew Bragg, a Moderate, said Australia had to stick to net zero and that keeping the Coalition together was important, but “not at any cost”.

In a signal that his faction is open to compromise, Bragg pegged his commitment to the Paris Agreement that he said called for net zero sometime in the second half of this century rather than by 2050.

“I don’t see how we could walk away from the Paris Agreement. I don’t see how we can walk away from our commitment to reduce emissions. We would be a pariah state,” Bragg told the ABC.

“Obviously, I support Sussan, and I think we need to show leadership now. We can’t backslide. The people of Australia are relying on us to hold this terrible government to account, and deliver policies which are reasonable alternatives.

“Net zero and the Paris Agreement are not causing the problems in Australia, the problems in Australia have been caused by the Labor Party’s terrible electricity and energy policies.”

Another Moderate, Senator Maria Kovacic, said on ABC TV that women leaders were judged more harshly than men across the globe.

“Ultimately, Sussan Ley has shown she has worked through lots of difficult issues since she became the leader,” Kovacic said.

Nationals senator Bridget McKenzie has also thrown her support behind Ley, telling Nine’s Today on Tuesday that “Sussan Ley has one of the most difficult jobs in the Australian parliament, following the last election, to rebuild the Liberal Party, and we want her to be successful because we believe that the Coalition is the best government for Australia is to prosper under.”

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