Japan likely spent up to ¥900 billion ($6 billion) on its second straight day of suspected currency intervention on Monday, bringing the total for yen-buying action since last month to as much as ¥9.2 trillion, according to market estimates on Tuesday.
Authorities' so-called stealth intervention in rapid succession has underscored their resolve in fighting what they have characterized as "intolerable and speculative" yen-selling, although the impact has proved short-lived.
Japan has the world's second-largest foreign reserves after China, at $1.238 trillion. But only a fraction is readily available for use, in the form of funds such as deposits parked with central banks and the Bank for International Settlements.