Pressure on Abbott mounts as three Australian MPs call for leadership change

It has been another forgettable day for Australian prime minister Tony Abbott, with several backbench MPs calling for a change of leadership on Tuesday evening.

Western Australian Liberal MP Dennis Jensen became the first to publicly request Abbott's resignation, before Queensland Liberal National Party members Warren Entsch and Mal Brough followed suit.

Only half way through his first three-year term as prime minister, Tony Abbott faces a revolt from within the ranks of his conservative government.

It comes after weeks of speculation regarding turmoil within the federal government, as poor polling results and the Coalition' s likely defeat in both the Victorian and Queensland state elections falls on Abbott's shoulders.

Although deputy party leader Julie Bishop confirmed earlier in the day that she would not run against Abbott if a leadership spill was called, there are suggestions that communications minister and former party leader Malcolm Turnbull may do so himself.

However, Fairfax Media reported on Tuesday night that Turnbull has told colleagues it is the backbench pushing for a change in leadership, not him.

Fairfax have also reported that internal estimates suggest as many as 30 MPs have indicated a desire for a leadership change, which could force the issue beyond Abbott's control when parliament returns next week.

They were claims supported by Jensen, who on Tuesday informed Fairfax Radio that many constituents had told him "Tony Abbott has to go."

Jensen continued, saying: "That is universal, that's my party members, that is my constituents. I'm getting people that are normally absolutely rusted on, they have voted Liberal all their lives and they are saying they will vote informal next time."

"They can't bring themselves to vote Labor or anything else, but they'll vote informal."

Earlier, Jensen was the first to openly state that he had lost faith in Abbott, saying that his decision to award Duke of Edinburgh Prince Philip an Australian knighthood last week had no impact on his judgment.

Entsch was the next to reveal he would like to see a leadership spill to see the issue resolved.

"It needs to be resolved," Entsch also told Fairfax Radio.

Entsch went on to suggest he would strongly support Turnbull if a leadership spill was called, although he would not put himself forward a role in challenging the prime minister.

Meanwhile, Brough has said he has "no intention of challenging the prime minister, " despite confirming that he had been approached to pit himself against Abbott if a spill was called over the weekend.

However, speaking on Tuesday, Brough did state that Abbott no longer has his full support.

"I listened to the National Press Club speech yesterday... there were a couple of things at least that weren't covered and for that reason... he does not have that unequivocal support, it's a critical support," Brough told Fairfax Media.

Abbott on Tuesday ruled out a leadership ballot, saying he was not prepared to have a ballot that could show how many of his party colleagues support his leadership and how many were prepared to back a rival. Endi