Financial markets were braced for further intervention by the Japanese authorities yesterday after the yen made its largest one-day gain so far this year. The yen's rise, from about 106 against the dollar to 102.2, took the currency well above levels at which the Bank of Japan has moved in to prevent further appreciation.

The yen also hit highs against the euro. Analysts said that such was the significance of the euro falling below the psychological 100-yen barrier - which the market had unsuccessfully tested earlier in the week - that once it was breached, the yen rocketed as high as 97.57 against the euro.