Shortly after the market opened, the benchmark S&P/ASX200 share index was down 48.1 points, or 1.3pc, to 3761.1.

The market's fall comes after US stocks ended the day decisively lower after gyrating for much of the day.

The Dow Jones Industrial Average lost 2.4pc and the broader S&P500 index shed 3.2pc, sapping a prospective rally for local shares.

Meanwhile, the Australian dollar could still fall below the US 60 cents mark today, despite reports the central bank would act again.

Such a fall would take the dollar back to six-and-a-half year lows, before the start of the resources boom driven by demand from China.

The Reserve Bank intervened in currency markets again to support the Australian dollar as it slid towards fresh five-year lows against the US dollar, a spokesman said.

The spokesman said the central bank was providing liquidity in an illiquid market.

This is the third consecutive day that the central bank has entered to prop up the beleagured Australian dollar, which has lost more than 35pc against the US dollar since peaking in July.

"There is psychological support at US60c, however, the market is paying very little attention to any technically significant levels at the moment," said Tom Averill, senior consultant at the currency trading firm HiFX.

He would not rule out the Australian dollar dipping into the 50s.

"There's a good chance of seeing 57 US, even 55 US cents - not necessarily today."

From there, stop losses, or contracts set up to sell once a currency hits a specified low, could drive the Aussie lower.

"As soon as the Australian dollar breaks through 60 US cents, because of a lack of liquidity, you'll see 57 US cents very quickly."

"Today, it will be interesting to see whether the RBA will be intervening again," he said. "They may well be in the market again."

The dollar recently bought US60.37c despite reports the Reserve Bank was encouraging currency traders to expect it would intervene again to buy up the currency if it weakens.

Against the soaring Japanese yen, a popular haven during the current bout of financial fear, the Aussie dollar was recently buying 56.43 yen, not far from its record low 55.1 yen reached in recent days.