The Japanese yen posted its strongest one-day gain against the U.S. dollar in nearly two years on Thursday after what market sources said was official intervention by Japanese authorities during New York trading hours. According to Reuters, the move was coordinated with South Korean authorities and lifted the yen sharply from levels close to a four-decade low.
The sudden appreciation comes after repeated warnings from Japanese officials that they were prepared to step into the foreign exchange market without prior notice. The intervention follows Japan's record currency support operations earlier this year, when authorities spent roughly $70 billion to stabilise the yen.
