By Leika Kihara
WASHINGTON (Reuters) - Japanese Finance Minister Katsunobu Kato issued a warning against currency speculation on Wednesday, expressing concern over "one-sided, rapid" moves in the currency market that have been driving down the yen's value.
"It's important for currency rates to move stably. We are watching exchange-rate moves with heightened vigilance, including for any speculative moves," Kato told reporters after attending the first-day session of the Group of 20 finance leaders' gathering.
Kato said the G20 finance leaders did not discuss currency rate moves at Wednesday's meeting, and are unlikely to do so at the second-day session on Thursday.
The dollar climbed above 153 against the yen for the first time in nearly three months on Wednesday, as solid U.S. data diminished market expectations of aggressive interest rate cuts by the Federal Reserve.
Japan last conducted yen-buying intervention in late July to support its currency after it tumbled to a 38-year low below 161 per dollar.
While a weak yen gives exporters a boost, it has become a source of concern for policymakers by hurting households and retailers through a rise in the cost of importing raw material.
The Bank of Japan's ultra-loose monetary policy, and signals from Governor Kazuo Ueda that he will be in no rush to raise interest rates from current near-zero levels, are also perceived by markets as contributing factors to the yen's weakness.