Calare MP Andrew Gee said he can't back Barnaby Joyce to remain as leader and "all bets are off".
Australia's embattled deputy prime minister, under pressure over an extramarital affair, faced a call to step down as leader of his party on Thursday, the first such call from a member of the party, which is part of the ruling coalition.
Prime Minister Malcolm Turnbull who is now in the US for a four-day trip to hold talks US President Donald Trump also deflected question on his deputy when he addressed media outside the White House.
Assistant Families Minister David Gillespie could put his hand up to replace Mr Joyce amid reports the NSW Nationals MP has indicated to colleagues his willingness to run if the party leader resigns.
A furious Turnbull, who relies on the smaller National Party to govern, has slapped a formal ban on sex between cabinet members and their staff in the wake of the Joyce affair.
They did not deny he was set to resign, despite repeated opportunities to do so.
His decision to call a media conference for later on Friday, confirmed by his party, came after a new allegation of sexual harassment was made by an unidentified individual.
Speaking in Washington DC, Mr Turnbull declined to publicly back Mr Joyce, saying "leadership of the National party is a matter for the National party".
The scandal has caused headaches for the coalition government, which had to call in Liberal minister Mathias Cormann to act as prime minister while Malcolm Turnbull is in the USA after Joyce took personal leave.
When contacted for comment yesterday, Mr O'Dowd said the National Party "meets each and every Monday in the party room during sitting weeks".
"At this point in time he should take a step back and stand down and be on the back bench", Broad told ABC radio.
"Andrew Broad has expressed these sentiments before", Joyce said.
Broad said that if Joyce has not stepped down by Monday, he intends to move a motion to spill the leadership, meaning Joyce is nearly certain to face a challenge on Monday.
"The office of Deputy Prime Minister is the second highest in the land, it requires character, and I believe he has failed that test", Mr Hastie said.