"They're talking about looking at policy changes but not actually implementing them yet," Lucas said.
China-focused resources companies were hit hard, as was financial services company AMP.
Nearly A$1.9 billion has been wiped off the market value of wealth manager AMP after it warned of a fall in its first half profit.
AMP shares fell 64c, or 12.8 per cent, to $4.34.
Mining giant BHP Billiton fell 3.4 per cent to $31.35 while Rio Tinto shares lost 2.1 per cent to A$51.54.
It came after Rio Tinto announced it has taken its diamonds business off the market.
Gold miner Newcrest closed below A$10 for the first time in a decade, losing 7.9 per cent to A$9.53 while Fortescue Metals shares fell below A$3 for the first time since September last year, finishing the day 4.2 per cent lower at A$2.92.
Banking stocks were also in the red, with Commonwealth Bank losing 32c to A$65.74, ANZ shedding 3c to A$27.38. National Australia Bank gave up 30c to A$28.68 and Westpac fell 17c to A$27.55.
Shares in supermarket group Metcash rose 4.9 per cent to A$3.61 after a 6.9 per cent profit lift.
- AAP