Japanese firms have shut factories in China and urged expatriate workers to stay indoors in the wake of angry protests over a territorial dispute.
Japan on Thursday said it would ban people entering the 20km evacuation zone around the Fukushima Daiichi nuclear plant north of Tokyo.
Analysts suggest power blackouts will ultimately cause the biggest economic damage to Japan, a vital player in the global manufacturing supply chain.
New Zealand's Edmund Hillary, who along with Nepal's Tenzing Norgay Sherpa became the first to conquer Mount Everest, died in hospital on Friday. He was 88. New Zealand flags flew at half mast at Scott Base in Antarctica on Friday, mourning the loss of one of the greatest adventurers of the 20th century.
The dollar failed to make gains against the euro and yen on Tuesday despite a rally on Wall Street as players remained sceptical of chances of a strong US economic recovery.