Malcolm Turnbull supporters believe they are within striking distance of ousting Tony Abbott from the Liberal leadership.

The Prime Minister sparked a backlash with a controversial “captain’s call” on Sunday in bringing forward a meeting to consider a leadership spill motion to Monday morning.

Liberal members were due to meet in Canberra on Tuesday to vote on a spill of the leader and deputy leader positions moved by West Australian backbenchers Luke Simpkins and Don Randall.

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Mr Abbott said he had brought forward the meeting to end the uncertainty before parliament resumed.

“The only question for our party is do we want to reduce ourselves to the level of the Labor Party in dragging down a first-term Prime Minister,” he told reporters.

If the spill is successful, Mr Abbott is likely to face a direct challenge for the leader’s position from Mr Turnbull.

Attending a party fundraiser with deputy leader Julie Bishop in Sydney, Mr Turnbull strongly hinted he would stand, saying that if the leadership was declared vacant “any member … can stand whether they are a minister or backbencher without any disloyalty”.

“The leadership of the Liberal Party is uniquely in the gift of the party room,” he said.

Ms Bishop could also put her hat in the ring for the leadership, telling reporters on Sunday: “I’m talking to my colleagues today and the party room will decide.”

Opponents of the spill motion suggested they had about two-thirds of the party room on their side, including ministers.

Supporters of the spill motion told AAP on Sunday they could count on at least 40 votes in the 102-member party room, excluding ministers.

Spill supporter Sharman Stone said on Sunday afternoon: “It’s all very confused.”

One senior Liberal told AAP that even 30 votes would provide “a base on which to build” for another challenge.

“The ultimate question is whether Tony is in a position to regain voter trust,” the MP said.

Mr Simpkins said if the Prime Minister’s supporters wanted to end the speculation they should allow the spill to go ahead and then vote for Mr Abbott.

Mr Turnbull said the decision to bring forward the meeting was a “captain’s call” by the Prime Minister.

Mr Abbott has been widely criticised for his “captain’s call” decisions including knighting Prince Philip and rolling out a $22 billion paid parental leave scheme, which has now been ditched.

Former minister and respected party elder Arthur Sinodinos said he would be supporting the spill motion.

“I believe we have to have this discussion,” he said, adding that it did not show respect to MPs to move the meeting forward.

Teresa Gambaro, a former Howard government minister, said MPs deserved to have their views heard.

“We cannot govern ourselves in an internal climate of fear and intimidation,” she said.

Treasurer Joe Hockey said there had been enough talk about the issue and the government needed to “get on with the job”.

“The Australian people want it resolved,” he said.

Any cabinet minister who supported the spill motion should resign, Mr Hockey said.

Backbencher Andrew Nikolic said the motion should be withdrawn.

MPs are holding out the option of a procedural move that the motion not be put, which would have to be voted on before the spill motion.

News Corporation boss Rupert Murdoch threw his weight behind Mr Abbott.

“Abbott, good guy, not perfect but no case for rebellion,” he tweeted.

-AAP