The Australian share market has opened lower as traders play it safe ahead of the outcome of the US budget negotiations.

At 1015 AEDT on Monday, the benchmark S&P/ASX200 index was down 24.6 points, or 0.53 per cent, at 4,646.7, while the broader All Ordinaries index fell 23.4 points, or 0.5 per cent, at 4,661.9.

On the ASX 24, the March share price index futures contract was down 17 points at 4,629 with 4,993 contracts traded.

US politicians are in negotiations to scale back a series of tax hikes and spending cuts that begin on January 1.

If the measures aren’t rolled back America could be pushed back into recession, a situation that has been called a fiscal cliff.