Asian shares ended a seven-day winning streak on Wednesday and commodities eased as investors fretted that lack of progress in talks on US budget woes risked putting the world's largest economy into recession.
MSCI's broadest index of Asia-Pacific shares outside Japan fell 0.5%, retreating from Tuesday's nearly three-week highs, with materials and energy sectors leading the declines.
Shares in resource-reliant Australian dropped 0.4%, easing from two-week highs, dragged lower by top miners on weaker gold and oil prices.
Australia's Bureau of Resources and Energy Economics said committed investment in major resources and energy projects, the main driver of Australian growth, still rose to A$268.4 billion at October 31 from A$260.8 billion at end-April, but the rise partly reflected higher project costs and masked a fall in the number of projects. A fall in commodity prices due to a drop-off in Chinese demand also weighed on shares.
"Markets don't really provide any sort of compelling investment value here at present because the grey cloud of uncertainty still overhangs the economic climate, in particular across Europe and the US, but also filtering into this part of the world as well," Jamie Spiteri, senior dealer at Shaw Stockbroking, said of Australian shares.
US stocks slid overnight after Senate Majority Leader Harry Reid expressed disappointment over little progress in dealing with the approaching "fiscal cliff" of deep cuts in government spending and big tax hikes early next year.
The Shanghai Composite Index slid 0.7% to its lowest in nearly four years, extending losses after closing below 2,000 points for the first time since January 2009.
The weak Chinese stock market, along with doubts over the U.S. ability to resolve its fiscal crisis, strengthened demand for sovereign debt, helping to push the 10-year Japanese government bond futures price to a 9-1/2-year high of 144.79.
"Although recent Chinese economic data is showing signs of improvement, Shanghai share prices seem to suggest that it is still far from a full-fledged recovery," said Takeo Okuhara, fund manager at Daiwa SB Investments.
Japan's Nikkei stock average fell 0.8%, after closing on Tuesday at a seven-month high.
The Nikkei had risen 8.8% over the past two weeks since the government announced a December 16 election. Japan's main opposition party is forecast to win power, and investors expect it will force the Bank of Japan into aggressive easing.
Europe lacks confidence
Tuesday's agreement by international lenders to cut Greece's debt offered relief that the country has averted an imminent bankruptcy, but scepticism over the lack of details on how Athens will carry out budget reforms to meet its new debt targets capped a rise in European shares and the euro.
The agreement on Greece is good news but it does not address medium-term financing and debt sustainability issues, Barclays Capital analysts said in a note.
"The uncertainty brought by this approach makes European assets, including the EUR, vulnerable to global growth risks. For that reason, we think the European muddle through amplifies the market's response to the fiscal cliff discussion in the US."
The euro was down 0.1% to $1.2932, slipping from a peak of $1.3010 hit on the Greece news on Tuesday, its highest level since October 31.
Worries over the fiscal crisis overshadowed positive US economic data that showed improvement in durable orders, the real estate sector and consumer confidence, which hit a 4-1/2-year high in November.
The dollar dropped 0.3% against the yen to 81.88. US crude futures were down 0.1% at $87.14 a barrel and Brent held steady at $109.90.
Spot gold inched down 0.1% to $1,740.75 an ounce after slipping on Tuesday for a second session.
Investors were sidelined in Asian credit markets, keeping the spreads on the iTraxx Asia ex-Japan investment-grade index little changed from Tuesday's levels.