The MSCI's broadest index of Asia-Pacific shares outside Japan fell 0.7 percent, with a 1.5 percent drop in its materials sector leading the declines.
Resource-reliant Australian shares fell 0.6 percent while Hong Kong, Shanghai and South Korean shares shed between 0.5 to 0.9 percent.
The dollar index measured against a basket of key currencies rose 0.3 percent, weighing on dollar-based commodities from oil to copper, while also weighing on gold.
The Australian dollar, often tied to investor risk appetite, slid 0.4 percent to $1.0408 and the euro fell 0.3 percent to $1.2937, but the safe-haven yen edged up 0.1 percent against the dollar to 78.08 yen.
The U.S. Federal Reserve and the Bank of Japan launched fresh monetary easing steps over recent weeks while the European Central Bank adopted a plan to buy bonds from euro zone states requesting assistance, to help drive down their borrowing costs.
Last week, markets oscillated between rallying on the fact central banks took action in light of weak economies, then falling as participants focused on the weak economic conditions that prompted these stimulus plans in the first place.
"The Fed-inspired euphoria and the reaction to that euphoria both appear to have run their course now, bringing markets to a near-term equilibrium level where players seek guidance for next direction," said Toru Yamamoto, chief strategist at Daiwa Securities.
"The markets are now in a broad framework of pitting the real economy against the reflationary policies," he said, adding that downside risks were growing amid uncertainty in Europe and wariness ahead of U.S. corporate earnings reports next month.
Ample funds added through further monetary easing should underpin markets, but prices of assets tied to economic fundamentals were likely to be capped, such as oil and copper.
U.S. crude fell $1.06 to $91.83 per barrel, while Brent futures dropped $1.02 to $110.40 a barrel.
London copper fell 0.9 percent to $8,206 a tonne.
"The optimism (over the measures) is gone and investors are starting to realise it's not backed by good economic data," said Jonathan Barratt, chief executive of BarrattBulletin, a commodity research firm in Sydney. "Investors are not confident, that is why they're punishing commodities, including oil."
Spot gold slumped 1.3 percent to $1,759.65 an ounce, retreating from Friday's high of $1,787.20 which was just barely below this year's high of $1,790.30 hit on February 29.
The Nikkei stock average dropped 0.7 percent as a firmer yen added to woes for automakers and other exporters, which have been under pressure due to a territorial dispute between Japan and China.
SPAIN AT CENTRE
News on Friday that Spain was considering freezing pensions and speeding up a planned rise in the retirement age raised hopes for the country applying for a bailout and lifted market sentiment, but uncertainty remained over whether and when such a move would come.
"Now that the game of guessing what central banks from around the world are going to be doing with their endless pools of liquidity, we are now back to guessing which country is going to be bailed out and when," said Neal Gilbert, currency strategist at GFT Forex in New Jersey, in a note.
Spain has displaced Greece from the centre of the euro zone debt crisis, as markets worry it may eventually need external aid to help resolve its problems. A credit review by ratings agency Moody's, due by end-September, could prompt such a move if Moody's downgrades Spanish debt to junk status.
But Spain insisted on Saturday it will not rush to seek a sovereign bailout, even as the country suffers from a high deficit, soaring debts, a banking sector burnt by the bursting of a real estate bubble and a deepening economic contraction.
At the same time, euro zone states are preparing to allow the bloc's permanent bailout fund, expected to come into force on October 8, to leverage its capital in the same way as its predecessor so it can rescue big countries if necessary, Der Spiegel said on Sunday.
Another uncertainty which has persisted as major economies took action is whether China will ease monetary policy, with its economy on course to show slower growth for the seventh straight quarter over the current period.
A senior official was quoted by state media on Sunday as saying that China plans to stick to its tight property sector policies and a nationwide rebound in home prices remains unlikely, reinforcing officials' reluctance to ease property market restrictions to bolster the economy.
Asian credit markets softened slightly, with the spread on the iTraxx Asia ex-Japan investment-grade index widening by 2 basis points.
Copyright @ Thomson Reuters 2012