US President Barack Obama Tuesday offered his congratulations to Australia's Prime Minister Julia Gillard, who held onto office after breaking a 17-day logjam that built up behind the inconclusive August 21 parliamentary elections.

In a telephone call, Obama expressed his commitment to the alliance between the US and Australia and the two leaders agreed to work closely on security and economic issues in the Asia-Pacific and around the world, the White House said in a statement.

'The president looks forward to working with Prime Minister Gillard at the (Group of 20) G20 and Asia-Pacific Economic Cooperation summits in November, and is confident that the US-Australian alliance will only grow stronger in the years ahead,' the White House said.

Two independents backed Labor, giving it the 76 seats needed to command a majority in the 150-member assembly and claim a second term Tuesday. After 17 days of bargaining, they decided the goodies Labor promised for their electorates were better than those on offer from Tony Abbott's conservatives.