The Japanese finance minister said on Tuesday his nation's currency was "strongly overvalued" as expectations grew that Tokyo would intervene to sell the yen.
"In principle, it is desirable for fundamentals to be reflected in the market, and in this sense, the yen is strongly overvalued," Yoshihiko Noda told a regular news conference.
"Its movement continues to be one-sided."
He made the remark after the yen climbed close to a post-World War II high.
Noda declined to comment on the prospect of currency-market intervention, but he said he has been "in touch" with overseas currency authorities.
The dollar fell briefly to 76.29 overnight, just pips away from its post-WWII low of 76.25 yen on March 17.
The greenback has since firmed and was trading at 77.52 yen in early Tokyo trade, but Japan remains ready to intervene at any point, a person familiar with the country's currency policy affairs told Dow Jones Newswires on Tuesday.
"Japan can conduct intervention at any time," the source told the wire.
But the source declined to say how close the authorities are to taking action, Dow Jones said.