That argument was dismissed by some of the Prime Minister's allies who insisted the onus was on the challenger to prove he had increased his numbers from the leadership ballot on Tuesday, which Mr Turnbull won by 48 to 35 votes. Loading The petition was passed from one MP to another on Wednesday evening, in a tactic similar to a move that forced Julia Gillard to call a ballot against Kevin Rudd in 2013. Because no copy of the petition was kept as it was handed between MPs, the document itself may never emerge, in another parallel with Labor’s “phantom petition” five years ago. Immense pressure was being brought to bear on MPs in Western Australia who had sided with Finance Minister Mathias Cormann and voted for Mr Turnbull on Tuesday, fuelling talk that some would switch camps and deliver victory for Mr Dutton.

Sources denied Senator Cormann, one of the party's leading conservatives and a friend of Mr Dutton, had withdrawn support from Mr Turnbull but the Finance Minister would not comment. Treasurer Scott Morrison has also kept his support for Mr Turnbull and those loyal to the Prime Minister insisted their numbers remained solid. One of the Prime Minister's allies argued that Mr Dutton would need 43 out of 84 party room members on the written document to justify a meeting on Thursday. "If they've got the same numbers they had the other day there's no point re-running the process," he said. Former home affairs minister Peter Dutton on the backbench in question time on Wednesday. Credit:Alex Ellinghausen

Another argued that few on the Prime Minister's side had seen the petition and nobody should assume a meeting would be held on Thursday based on frenzied reporting in the media about the document's existence. Illustration: Matt Golding In a move to heighten pressure on Mr Turnbull, assistant minister James McGrath insisted on resigning after the Prime Minister had declined to accept his initial resignation on Tuesday. Other frontbenchers continued to back the Prime Minister, with Social Services Minister Dan Tehan saying: “I will not vote against a sitting PM.” One of Mr Turnbull's supporters, Queensland MP Jane Prentice, dismissed the petition as she left Parliament House on Thursday night, saying she had heard the document only had nine signatures and there was no need for another ballot.

"I think people should stop thinking about themselves and think about the people of Australia," an angry Ms Prentice said. The moves came hours after five ministers who voted for Mr Dutton declared their loyalty to Mr Turnbull in Parliament, highlighting the rapid shifts within the party room and the bad blood on both sides of the vote. Loading The group consisted of Health Minister Greg Hunt, Trade Minister Steve Ciobo, Human Services Michael Keenan, Law Enforcement Minister Angus Taylor and Citizenship Minister Alan Tudge. One MP argued those five could not justify signing the petition to call for a second ballot after they had answered questions in Parliament about their support for the Prime Minister.

Those calling for a new ballot said the matter had to be resolved on Thursday. “If he does not go now this will go on, and on and on,” one of Mr Dutton’s supporters said of Mr Turnbull. The moves came as Mr Dutton faced growing questions over his eligibility to sit in Parliament because of his pecuniary interest in childcare centres that receive money from the Commonwealth. In a move that could fuel those doubts, Attorney-General Christian Porter declared he would seek advice from the Commonwealth’s top legal advisor, Stephen Donaghue QC, on whether Mr Dutton had a case to answer on his eligibility. “Given that today the subject of a member’s eligibility was raised in Question Time and in media reports, I determined to seek advice from the Solicitor-General on the issues raised,” Mr Porter said in a statement issued just as word spread of the petition.

Labor demanded answers in Parliament on whether Mr Dutton has fallen foul of section 44 of the constitution because of his pecuniary interest in childcare companies that received $5.6 million from the Commonwealth. Mr Turnbull insisted Mr Dutton had legal advice to assure him there was no issue but the Prime Minister conceded he had not seen the advice. Attorney-General Christian Porter went to Mr Dutton on Wednesday afternoon to discuss the facts surrounding the ownership of the childcare centres, delaying any decision on whether to get the formal legal advice. Mr Dutton left no doubt he was “working the phones” to build his numbers and made it clear he would move when he had a majority. “You don't go into a ballot believing you’re going to lose, and if I believe that a majority of colleagues support me, then I would consider my position,” he said in a radio interview on Wednesday morning.

Mr Turnbull insisted the vote on Tuesday should settle the matter. “The iron laws of arithmetic confirmed my leadership of the Liberal Party,” he said. Prime Minister Malcolm Turnbull is under pressure. Credit:Alex Ellinghausen Former prime minister Tony Abbott said the next leadership vote was needed “as soon as possible” while former international development minister Concetta Fierravanti-Wells said the government’s direction had to be reset quickly. “The most important thing for the Liberal Party into the future is to reclaim our base and therefore the sooner issues are dealt with the better,” Senator Fierravanti-Wells told Fairfax Media.