Investor sentiment turned positive after US House of Representatives Speaker John Boehner said he remained hopeful about an agreement to tackle the fiscal crisis by the end-of-year deadline.
The S&P/ASX 200 index inched up 0.2 percent, or 7.8 points, to 4,583.8, extending gains into a fourth straight session and marking its highest close since July 22, 2011. The benchmark climbed 0.4 percent on Tuesday. Top miner BHP Billiton Ltd climbed 1.0 percent after it said it would sell its interest in the Browse liquefied natural gas project to PetroChina Co Ltd for $1.63 billion. Rio Tinto Ltd gained 0.7 percent, and Fortescue Metals jumped 1.7 percent. Woodside Petroleum Ltd, the country's biggest energy producer, added 1.6 percent. Major banks all lost ground in afternoon trading, led by a 0.8 percent slide in Australia and New Zealand Banking Group. New Zealand's benchmark NZX 50 index was down 0.8 percent at 3,995.3.