Asian shares mostly fell Monday, with Tokyo slipping as emergency work to bring under control a crippled nuclear plant in Japan continued to be held up by high levels of radioactivity.
Emergency crews battling to avoid a wider nuclear disaster at the Fukushima No.1 plant, which was rocked by the March 11 quake and tsunami, have suffered several setbacks, with workers forced to evacuate by soaring radiation levels.
Tokyo slipped 0.36 per cent by the break, Hong Kong dropped 0.43 per cent, Seoul edged down 0.11 per cent and Singapore fell 0.34 per cent.
Sydney was flat and Shanghai rose 0.83 per cent.
Investors were upbeat last week as work to contain the Fukushima crisis appeared to be going well, but reports of rising levels of radiation have hampered workers' efforts, stoking uncertainty over how quickly the situation will be resolved.
"While last week was mostly about buying back of shares following the post-earthquake sell-off, investors will be paying a closer look at the specific fallout (on corporations) from the quake," Yutaka Miura, a technical senior analyst at Mizuho Securities, told Dow Jones Newswires.
Concerns over the Japanese crisis overshadowed another strong cue from Wall Street on Friday, where the Dow closed up 0.41 per cent thanks to an upward revision of the growth figure for the US economy in the last quarter of 2010.
The Commerce Department said the world's biggest economy expanded 3.1 per cent in the three months to December 31, up from the initial forecast of 2.8 per cent, adding to evidence the recovery there is gaining strength.
Hopes for the United States and calls by a senior Federal Reserve official on Friday for the central bank to return monetary policy to a more normal setting boosted the dollar.
The Fed in 2008 slashed rates to near-zero in a bid to lessen the impact of the global financial crisis.
In early Asian trade the dollar rose to 81.58 yen from 81.34 late in New York Friday amid hopes interest rates could rise at some point, while the euro slipped to $1.4057 from $1.4088.
Higher interest rates usually support a currency as they make it a more attractive investment proposition.
The European currency traded at 114.67 yen from 114.75 yen as it continued to be weighed by eurozone debt worries after Portugal last week failed to pass an austerity package, with many believing Lisbon will be forced to seek a bailout.
On oil markets, uprisings across the oil-rich Middle East and military strikes on crude exporter Libya kept prices higher.
New York's main contract, light sweet crude for delivery in May, rose 15 cents to $105.55 per barrel in the morning, while Brent North Sea crude for May gained 25 cents to $115.84.
Gold opened at $1,426.80-$1,427.80 an ounce in Hong Kong, down from Friday's close of $1,433.00-$1,434.00.