U.S. Senator Elizabeth Warren sent a letter to Treasury Secretary Bessent on August 13, requesting an explanation of the specific scale, legal basis, and estimated cost to U.S. taxpayers of the U.S. government's use of euro funds from the Exchange Stabilization Fund (ESF) to intervene in the Japanese yen on July 31. Warren also inquired whether the Treasury Department had communicated with the European Central Bank (ECB) before using the euro funds and requested Bessent to respond by August 28. Previously, Bessent had confirmed that the U.S. and Japan had jointly intervened in the foreign exchange market for the first time since 1998 to support the yen, but the specific amount of funds has not yet been disclosed.