Ley, who met Littleproud on Monday night, set out conditions for reuniting with the Nationals, with the central one being that the three Nationals who broke shadow cabinet solidarity over the government’s anti-hate legislation spend six months off the front bench.

This was unacceptable to the Nationals, who were drafting a general response to Ley on Tuesday afternoon.

Other conditions in Ley’s proposal were that the Nationals accept shadow cabinet solidarity, and neither the Liberal Party room nor the Nationals Party room could overturn a shadow cabinet decision.

The joint parties room would remain supreme, which was made clear by Ley in response to questions when she briefed the Liberal Party meeting on Tuesday morning.

Also in Ley’s plan was for the Liberals to hold the portfolio of shadow assistant treasurer, in exchange for the Nationals taking the skills portfolio.

Littleproud said in a statement the Nationals would “take our time to consider the details” of the written offer that had been put to them.

“The Nationals are united in our endeavours to reset the Coalition, but we won’t be providing updates on any negotiations through the media.

"The negotiations are ongoing and we will always be constructive and act in good faith. It’s important we take the time to get the settings right.”

Meanwhile in Adelaide, Hanson announced former Liberal Cory Bernardi would lead the One Nation’s upper house ticket for the state election.

The party holds no SA state seats. Sarah Game, elected to the upper house in 2022 as the first One Nation candidate to win a seat in the SA parliament, defected last year to become an independent. Game cited problems with how the party’s brand was perceived.

The party will also contest all lower house seats.

Bernardi, a former senator, defected from the Liberals in 2017 to sit on the crossbench. His subsequent attempt to win support for a new conservative movement failed.

In the latest Redbridge poll in the Australian Financial Review, One Nation was on 26% nationally. Its spiking support, reflected in other polls, has discombobulated the Nationals, and added to pressure for a leadership change in the Liberals from the centrist Ley to a conservative.

While the SA Labor government is assured of victory against an opposition that has been beset by problems and leadership turnover, the election will test how One Nation’s voting surge translates to an actual election.

Former senator Nick Xenophon tried to transfer his personal popularity and the strong performance of his team nationally into trying to win seats at the 2018 South Australian election. The effort crashed dramatically.

The Coalition break was reflected for the first time in parliament on Tuesday as the Liberals and Nationals sat in their separate blocks.

Earlier, the leadership tensions were an undercurrent at the Liberal party meeting. “You could cut the air with a knife”, one source said.

Some sources believe Ley is not heavily invested in putting the Coalition back together because she wants to be able to hand out more posts to Liberals to lock in votes ahead of a leadership contest. She has said she will announce a permanent all-Liberal frontbench if there is not agreement to re-form the Coalition this week.

Also, some moderate Liberals (on whose support Ley depends) are not keen to have the Nationals back in the fold, believing the Liberals would have better appeal in the cities if they are not tied to the minor party.

Angus Taylor’s supporters are keeping open the option of a challenge to Ley next week. It will depend on whether Taylor – now the only conservative candidate after Andrew Hastie’s withdrawal – is confident he has the numbers, which are close. Ley is likely to take another polling hit at the weekend with the release of Newspoll on Sunday.

Image - Nation Senator Pauline Hanson with former Senator Cory BernardiOne Nation Handout Image