Opposition finance spokesman Andrew Robb says a coalition government will make decisions about looking after "the world's poor" once it's achieved a sustainable surplus.
The coalition says it will reduce foreign aid spending by four-and-a-half billion if it wins the election.
But Mr Robb says it's not a cut to foreign aid but a reduction in future spending growth.
He says it's stupid for Australia to borrow from overseas countries, pay interest on that money and then give it back.
Foreign Minister Bob Carr says cutting back foreign aid will diminish Australia's security.

