The Japanese yen steadied on Wednesday after its most volatile few days in months following historic joint intervention by Tokyo and Washington. The dollar hit its lowest against the Japanese currency in three months after joint purchases on Friday by Tokyo and Washington — the first yen-buying intervention for U.S. authorities since 1998 — and fell further on Monday. The yen was steady at 157.55 per dollar, slightly stronger on the day, having fallen 0.4% on Tuesday. U.S. Treasury Secretary Scott Bessent said the U.S. would do "whatever it takes" to support Japan's efforts to stabilise the yen, while CIBC Capital Markets' Jeremy Stretch described intervention as a containment exercise unless the Bank of Japan hikes rates more aggressively, markets price in fewer Fed rate increases, or oil prices fall. The dollar index was 0.1% lower at 99.71, pressured by revived hopes of an end to the war in Iran and lower oil prices around $80 a barrel, which reduced safe-haven demand and lowered the probability of a Fed rate hike in September to just below 60%.