Rudd's deputy, Julia Gillard, was elected leader in an uncontested vote about 12 hours after she surprised many colleagues by challenging a prime minister who until recently had been among the country's most popular.

Rudd was one of the West's few Chinese-speaking leaders and helped broker the Copenhagen climate change agreement, but his quick removal showed his party had lost faith he could win a second term in national elections due within months.

Many foreign policies, including Australia's 1,500-strong military contribution to the war in Afghanistan, are not likely to change under Gillard.

But the leadership change immediately eased hostilities between the government and big mining companies over a proposed tax on so-called super profits from burgeoning mineral and energy sales to China and India. Gillard quickly ended an advertising campaign that promoted the tax, keeping a Labor promise that Rudd broke to never use taxpayers' money for political advertising.

The world's biggest miner, BHP-Billiton, responded by suspending counter-advertising that claimed the new tax would cost jobs and investment in the mineral sector, which is driving Australia's economic growth.

Gillard said her government is willing to negotiate on the proposed tax. Opinion polls show the tax debate is doing increasing harm to the government's re-election chances.

Rudd rode high in opinion polls until he made major policy backflips, including shelving plans in April to make Australia's worst polluters pay for their carbon gas emissions.

An airplane towed a banner over Parliament House on Thursday which made an apparent reference to the backflip: "Julia aim higher on climate." But Gillard has not committed to pressing ahead with the government's so-called emission trading scheme in which polluters would buy and trade permits for every ton of carbon gas they produce. The Senate has twice rejected the legislation.

She said that as prime minister she would seek a community consensus on how carbon pollution should be priced.

An emotional Rudd, flanked by his wife and three children, gave his final speech in the prime minister's court yard at Parliament House on Thursday, saying he was proud that his first act in government in 2007 had been to ratify the Kyoto protocol for reducing greenhouse gas emissions.

Gillard and her new deputy, Wayne Swan, were sworn into their offices by Australia's first female governor-general, Quentin Bryce, within hours of the ballot. Swan retains his key financial portfolio as treasurer and will fly to Canada on Friday for a summit of Group of 20 major economies in Rudd's place.

Gillard has been instrumental in most of the government's decisions to date as part of Rudd's four-member inner circle that included Swan and Finance Minister Lindsay Tanner. Tanner announced Thursday he was quitting politics at the next election for personal reasons.