Leadership hopeful Peter Dutton has asked Prime Minister Malcolm Turnbull to convene a meeting of the Liberal Party on Thursday morning where he will challenge for the leadership of the party and the country.

Mr Dutton announced his intentions at a brief press conference at Parliament House in Canberra this morning. He later said he would not have issued the challenge unless he believed he had the numbers required for victory.

The prime minister has reportedly refused the meeting.

Senior ministers Matthias Cormann, Michaelia Cash and Mitch Fifield spoke to the media shortly after parliament opened on Thursday to reveal they had approached the prime minister and told him they believed he had lost the confidence of the majority of his party room.

This fresh challenge follows an attempted late-night coup from supporters of Mr Dutton late last night.

His camp attempted, unsuccessfully, to deploy whispers and media manipulation to trigger a vote.

Late on Wednesday it emerged a petition was circulating to demand a party room meeting “as soon as practicable” – the same tactic used by Kevin Rudd to roll Julia Gillard in 2013.

Claims circulated of the critical defections of Mathias Cormann, Michaelia Cash and Dan Tehan were later denied. Only a junior minister, James McGrath, resigned overnight.

“Fake news” was how one Liberal MP put it as he walked to his car on a chilly night in Canberra. Another denied the existence of the petition.

There were grand promises of ‘having the numbers’, but only a small number (as few as nine according to Liberal MP Jane Prentice at 9pm) signed the letter. By convention, it needed 43 signatures to appear conclusive.

Old-fashioned bully tactics were also alleged. Four female MPs complained to the Whip’s office, saying they felt intimidated when asked to sign the petition, Phil Coorey of the Australian Financial Review reported.

“A distinct lack of class” and “the most shambolic leadership coup I’ve ever seen” was how political analyst Peter van Onselen put it. A Labor MP went further: “F—ing debacle.”

The agitators may have felt these tactics were necessary after momentum for the putsch appeared to slow on Wednesday afternoon when Mr Dutton’s thought bubble of a GST-free power bill idea was trashed by the Prime Minister, the Treasurer and Labor.

“An absolute budget blower” was how Scott Morrison put it.

“You know you’re an economic illiterate when even economic dunce Scott Morrison manages to lay a blow on your chin,” his Labor counterpart, Chris Bowen, fired back.

Added to this were constitutional doubts over Mr Dutton’s eligibility to sit in Parliament, raised by Labor and aided by Mr Turnbull. These claims relate to Mr Dutton’s family trust fund, which allegedly receives subsidies from the government through two child care rebates. This could prove a banned “pecuniary interest” under Section 44, two constitutional experts warned.

Mr Turnbull pulled back his attack dog, Christopher Pyne, when Labor went after his rival over Section 44. When asked about a referral to the High Court, the PM said he had “no reason … to believe” Mr Dutton was in breach of Section 44. An emphatic refusal it was not.

Following question time, Attorney-General Christian Porter referred the matter to the Solicitor-General, the government’s chief legal adviser, for advice.

Tony Abbott questioned whether the claims against Mr Dutton had been manipulated by a “despairing incumbent”.

“Whether these are more dirty tricks from a Labor party which is desperate not to have Peter Dutton as its opponent, or whether this is just one last throw from a despairing incumbent, I just don’t know,” Mr Abbott told 2GB radio.

2GB listeners may have got their own taste of trickery earlier in the day, when host Ray Hadley appeared to let slip that he was reading a message from Peter Dutton, attacking Mr Morrison.

“Scott Morrison is now running around trying to put a ticket between himself and Peter Dutton together to try to challenge Malcolm Turnbull,” Mr Hadley read on air.

“He’s told those he’s lobbying he won’t serve as my …”. Here he stopped, correcting himself. “… As the deputy to Peter Dutton. The radio host later denied the message was from Mr Dutton.

If Mr Dutton is successful in a challenge on Thursday, the leadership may prove a poisoned chalice.

There have been reports that crossbench MPs Rebekha Sharkie and Cathy McGowan may withhold support on confidence and supply, and that the National Party will demand a new coalition agreement.

And then there was the popularity question. New polling from Roy Morgan put Mr Dutton behind both Mr Turnbull and Bill Shorten in the ‘Better PM’ stakes.

And, looking ahead to the next election – likely in October or May, according to ABC election guru Antony Green – Mr Dutton faces a grim prospect, according to his own side.

The war chest is bare and many National and Liberal preselections are yet to be finalised, backbencher Ken O’Dowd admitted as he left Parliament for the night.