Japanese monetary authorities have spent more than 3 trillion yen intervening in the currency market since late May, according to statistics compiled by the Finance Ministry.
During the yen-weakening campaign, the exchange rate has gone from 125 yen.61-64 to the dollar on May 21, the day before the intervention began, to 119 yen.55-57 at 5 p.m. Monday.
The most recent dollar-buying spree, carried out by the Bank of Japan on behalf of the ministry, came Friday.