The Aussie market extended its recent slide in an extremely volatile session today.

Stocks were pummelled on the open before staging a huge rally after G20 leaders pledged to resolve Europe's debt crisis.

The comeback proved short-lived however, with the market sinking back into the negative by session close.

Resource stocks again suffered the heaviest punishment amid deteriorating prospects for commodities; BHP lost 3% and Rio Tinto dropped 3.8%.

Nexus recovered some of yesterday's steep losses (+29.2%) following a favourable assessment of its Crux project by global consulting firm, RISC.

The big banks were mostly lower, although they didn't fare as bad given the turmoil in the European financial sector.

CBA managed a 0.9% gain for the day.

The ASX 200 slumped 62 points (-1.6%), closing at 3903.

Today's falls capped a tumultuous week that saw the market plunge 5.9%.