The Australian sharemarket was one per cent weaker mid-session following heavy offshore falls after Wall Street plunged overnight.
At 10am, the benchmark S&P/ASX200 index was down 44.3 points, or one per cent, at 4344.1, while the broader All Ordinaries index was down 46.3 points, or one per cent, at 4364.4.
On the ASX 24, the December share price index futures contract was down 44 points at 4,356, with 19,837 contracts traded.
Comments by US President Barack Obama about raising taxes for the wealthy along with weak retail and manufacturing economic data there and in Europe have been cited as triggers for "risk-off" falls.
IG Markets market strategist Stan Shamu said he thought the Australian market was performing okay considering how heavy the falls had been in the US.
The Dow Jones Industrial Average dropped 185.23 points (1.45 per cent) to 12,570.95, its lowest close since June 26.
The broad-market S&P 500 lost 19.04 (1.39 per cent) at 1355.49, while the tech-rich Nasdaq Composite gave up 37.08 (1.29 per cent) at 2,846.81.
"There are a few bright spots and all things considered after looking at the big drop on Wall St are actually not doing too badly finding some support in the 4,350 region," he told AAP.
"The sharp slide in the Aussie dollar will give some sectors some support as well ... unfortunately most cyclical names will continue to struggle until we get a bit more clarification on the fiscal cliff issues."
The "fiscal cliff" refers to the huge tax hikes and spending cuts that automatically come into force on January 1, and could send the world's largest economy back into recession, if US Republicans and Democrats can't reach a compromise.
Mining giants BHP Billiton had dived 61 cents to $33.12, Rio Tinto plunged $1.31 to $56.54 and Fortescue dropped 4.5 cents to $3.955.
The four major banks were all worse at noon.
ANZ had shed 20 cents to $24, National Australia Bank fell 23 cents to $23.01, Westpac lost 27 cents to $24.58 and Commonwealth Bank was 72 cents lower at $58.37.
Airline Qantas had gained four cents, or 3.25 per cent, to $1.27 after it announced it would spend $100 million to buy back about four per cent of its issued stocks and would repay $650 million of debt ahead of its due date.