Japan's Nikkei index closed down 1.04 per cent on Monday as concerns about the strength of the yen, which last week struck a postwar high against the dollar, weighed on exporter shares.
The headline index at the Tokyo Stock Exchange lost 91.11 points to 8,628.13, its lowest close since a March 15 plunge to 8,605.15 in the wake of the March 11 earthquake and tsunami and a subsequent nuclear accident.
The Topix index fell 1.18 per cent, or 8.85 points, to 742.84.
Investors closely watched the yen's movement against the dollar, as the safe-haven unit's strength, seen as a reflection of weak global risk appetite, encouraged selling of exporters, whose repatriated profits are eroded by a strong domestic unit.
The dollar on Friday fell to a post-war low against the yen of 75.95.
But a stronger greenback, quoted at 76.76 yen about 0600 GMT compared with 76.50 yen late Friday in New York amid renewed threats of intervention from Tokyo, provided better support for stocks on Monday, said dealers.
"It's a tug-of-war between caution and expectations for a global equity rebound later in the week," Yutaka Miura, senior technical analyst at Mizuho Securities told Dow Jones Newswires.
Miura noted that markets were anticipating a key speech from US Fed Chairman Ben Bernanke scheduled for Friday, which could offer hints of further measures to soothe roiled markets in the world's biggest economy.