Asian stocks fell to one-month lows on Friday and the yen rebounded broadly as extreme volatility in the Nikkei kept investors on edge.
MSCI's broadest index of Asia-Pacific shares outside Japan shed 0.4 percent and reached levels not seen since April 19, extending Thursday's 2.2 percent fall. Australian shares underperformed, sliding 1.6 percent.
"There's a lot of volatility… from Japan, which is not good for market stability or confidence," said Stan Shamu, market strategist at IG in Melbourne.
European stocks are set to fare better though with the futures market pointing to a rebound as bargain hunters move in following the previous session's sharp selloff.
Having swung from gains of 3.6 percent to losses of 3.5 percent, the Nikkei ended the session 0.9 percent higher. It was down 3.5 percent for the week and some 8 percent off a 5-1/2 year peak touched on Thursday before starting to plunge.
Still, the Nikkei has soared nearly 70 percent since mid-November, when Shinzo Abe, who became prime minister the following month, proposed aggressive monetary and fiscal policies to revive the world's third-largest economy.
"The fact the market has had such a huge run over a relatively short period has left it incredibly vulnerable," said Shane Oliver, strategist at AMP Capital in Sydney.
"It's often the nature in bull markets where you have a steady upwards trajectory and investors get long in their positioning." he said. "Then some uncertainty appears and suddenly they have to close their positions which causes these sharp setbacks."
Those uncertainty surfaced on Thursday after HSBC's preliminary "flash" survey showed Chinese factory activity declined in May for the first time in seven months and Federal Reserve Chairman Ben Bernanke hinted that the U.S. central bank could soon scale back monthly bond purchases.
Two senior U.S. central bankers have since sought to soothe market fears, saying the Fed will not hastily withdraw its policy stimulus and the pace of bond purchases could be adjusted up or down depending on how the economy fared.
Bank of Japan (BOJ) Governor Haruhiko Kuroda on Friday said the bank had no specific targets for stock prices and the level of the yen and will not comment on day-to-day moves.
However, Kuroda said the bank will try to tame volatility in the bond markets through flexible market operations and enhanced communication with participants.
Japanese government bonds closed slightly lower on the day after a volatile session. The benchmark 10-year JGB futures fell 0.21 points to 142.30 while the 10-year cash bond yield rose 0.5 basis point to 0.835 percent.
YEN UP
Among the major currencies, the yen rose as the turbulent Nikkei spooked yen-sellers. That drove the dollar down 0.3 percent to 101.66, while the euro shed 0.4 percent to 131.52 yen.
The euro was up 0.1 percent against the dollar at $1.2942 .
Commodity currencies such as the Australian dollar were off lows, but their outlook remained shaky given worries about Chinese growth.
The Australian dollar fell 0.5 percent to $0.9688, but was off Thursday's trough of $0.9593. Support is seen around the 2012 nadir of $0.9581, and a break there would take it back to lows not seen since October 2011.
Commodities were calmer with copper up 0.3 percent at $7,323 a tonne following a 2.3 percent slide, gold was a touch softer at $1,388 an ounce.
Brent crude was also little changed at $102.35 a barrel, having plumbed a three-week low of $100.64 in the previous session.
