Canberra, Sep 14 (IANS): Senior cabinet minister Malcolm Turnbull was on Monday set to become Australia's 29th prime minister after toppling Tony Abbott in a Liberal leadership ballot at Parliament House in Canberra.

Earlier in the day, Turnbull resigned from the Cabinet in an attempt to force a leadership ballot and announced plans to contest the Liberal leadership, ABC reported.

Foreign Minister Julie Bishop also defeated Kevin Andrews in a ballot for deputy Liberal leader.

Before the vote -- which he won 54 votes to 44, Turnbull said he had been under sustained pressure to put his name forward.

"Now this is not a decision that anyone could take lightly. I have consulted with many, many colleagues, many Australians, many of our supporters in every walk of life," Turnbull said.

"This course of action has been urged on me by many people over a long period of time."

"It is clear enough that the Government is not successful in providing the economic leadership that we need. It is not the fault of individual ministers," he added.

"Ultimately, (Tony Abbott) has not been capable of providing the economic leadership our nation needs. He has not been capable of providing the economic confidence that business needs."

Turnbull was expected to be sworn in after Mr Abbott writes to the Governor General and resigns.