CANBERRA - New Australian Prime Minister Julia Gillard pledged to end a mining tax row as soon as possible after spending her first day in power speaking to world leaders and assuring Washington of Canberra's commitment to Afghanistan.

The Labor government appointed Gillard as prime minister on Thursday, fearing defeat at elections later this year as voters deserted incumbent Kevin Rudd over his handling of the tax row and a failed climate policy.

Global miners such as BHP Billiton and Rio Tinto say a planned 40 percent "super profits" tax will damage the resource-dependent economy which underpinned Australia through the global financial crisis.