U.S., Japan Mount Rare Joint Yen Support; Currency Jumps 4%

U.S. Treasury Secretary Scott Bessent said Washington and Tokyo have carried out a coordinated foreign-exchange intervention to support the yen, a step markets have not seen for more than a decade. The action followed the yen's slide to its weakest level versus the dollar in 40 years. After the intervention, the currency rebounded about 4% to roughly 157.5 per dollar. The last comparable joint operation dates to 2011, when the two countries intervened after Japan's earthquake and tsunami. According to Bessent, the coordinated move was confirmed publicly around Aug. 3 and included U.S. purchases of yen in the open market. Part of the buying was financed by selling euros, a tactical choice that spread the impact across multiple currency pairs instead of focusing solely on USD/JPY. Japan's Ministry of Finance and the Bank of Japan worked in tandem on their side, marking a genuinely bilateral effort rather than the solo Japanese interventions traders have become used to. Bessent said the U.S. is prepared to act again: "We will not hesitate to participate in further joint intervention," he said. President Trump also voiced support, saying, "We're always there for Japan." The development carries an added twist: before joining the Treasury, Bessent reportedly made about $1 billion betting against the yen while managing money for George Soros. A sharply weaker yen is not only a Japan problem. It can disrupt trade balances across Asia, pressure regional currencies, and spill into U.S. Treasury markets as Japanese investors—among the largest foreign holders of U.S. government debt—adjust portfolios to manage currency swings. For crypto investors, the yen's plunge reflects diverging policy paths, with the Federal Reserve keeping interest rates relatively high while the Bank of Japan has maintained comparatively low rates. The 4% rebound removes one source of global financial strain, a backdrop that often supports risk assets, including crypto. A steadier yen also reduces the likelihood that Japanese institutions will need to sell overseas holdings to offset currency losses at home. The euro-funded element adds another angle to watch. If euro selling contributes to weakness in the single currency, European Central Bank officials may take issue with the euro being used as a financing tool for another country's currency support.