The yen surged past the key 155 per dollar threshold, triggering stop‑loss orders and pushing the currency toward its strongest level this year. After a 0.5% rise to 153.53 on Tuesday, gains for the month topped 4%, making the yen the top performer among G‑10 currencies. Analysts credit expectations of tighter Bank of Japan policy and possible intervention from Treasury Secretary Scott Bessent and Finance Minister Satsuki Katayama for the rally.

Technical momentum now points to 152.27 and 152.10, with traders noting thin liquidity and a potential unwind of yen‑funded carry trades. While overnight index swaps price a 97% chance of a 25‑bp BOJ hike, structural headwinds—wide Japan‑US rate gaps and trade deficits—could limit durability. Market participants are watching U.S. inflation data and BOJ board member Kazuyuki Masu’s speech, with the next BOJ policy meeting slated for next week.