Japan-US yen intervention is first joint currency action since 2011

Tokyo and Washington stepped into currency markets together for the first time in 15 years, reversing two months of yen losses in two days.

Japan and the US intervened jointly to support the yen for the first time since 2011, lifting the currency more than 4 percent off a 40-year low near 164.

"The significance of recent developments may not be the intervention itself, but the message it sends: markets are increasingly coming to believe that excessive yen weakness is no longer viewed as solely Japan's problem," said Masayuki Nakajima, senior currency strategist at Mizuho Bank in London.

Japan's finance ministry confirmed the coordinated action on Monday, saying it "countered excessive volatility and disorderly movements" in the yen. The Bank of Japan held its policy rate at 1 percent, the highest since 1995, in an 8-1 vote, while Governor Kazuo Ueda opened the door to further hikes at upcoming meetings. Tokyo spent about 8.45 trillion yen ($58.97 billion) buying yen on Jul 30, the largest single-day intervention on record, and the Federal Reserve Bank of New York sold euros to buy yen on behalf of the US Treasury the following day. Treasury Secretary Scott Bessent, whose handwritten note at a cabinet meeting read "Buy Japanese Yen (JPY) $5-10 bil," had called the yen "very undervalued." The currency traded near 157 per dollar, its strongest since mid-May, after President Donald Trump said the US was helping Japan "as a sign of friendship."

The coordinated action raises the stakes for anyone betting against the yen, but strategists caution that intervention buys time rather than reverses the fundamentals that drove the currency to its weakest since 1986. Goldman Sachs strategists led by Kamakshya Trivedi said authorities would likely intervene again if the yen unwinds recent gains, while the wide gap between Japan's 1 percent policy rate and the US upper bound of 3.75 percent keeps pressure on the currency.

A Rare Show of Coordination

The joint intervention marked the first time since 2011, when the two countries acted together after the earthquake in eastern Japan, that Tokyo and Washington moved in tandem to support the yen. The US Treasury told a number of banks it might intervene again, and South Korea separately stepped in to buy its won on Thursday, a sign of broader regional coordination. Japan had intervened in April and May, buying yen with only a brief rebound, and the BOJ's June hike to 1 percent gave the currency little lasting boost.

Intervention Buys Time, Not a Turn

Strategists see the intervention as a short-term stabilizer rather than a turning point. "It seems likely that authorities would intervene further in coming days if the yen begins to unwind the recent move, as was the case in May of this year," Goldman's Trivedi wrote. "We continue to think intervention is an effective tool for authorities to buy some time before fundamental factors turn more positive." "Given joint action with the US is still ongoing, USD/JPY could decline below 155 if stop losses are triggered," said Moh Siong Sim, a strategist at Oversea-Chinese Banking Corp. "But the success of intervention in reversing the JPY weakness depends on whether intervention is complemented by or is a substitute for more hawkish BOJ stance."

The yen's depreciation has squeezed businesses and consumers through higher import costs, and a failure to arrest the slide would spill into global markets, with volatility in Japanese government bonds jolting Treasuries earlier in 2026. "The prospect of a larger, more lasting allocation shift could pose a larger threat to Treasury yields," said Rebecca Patterson, a senior fellow at the Council on Foreign Relations. "It's in Bessent's interest to convince Japan not to take that step." "The Finance Ministry's intervention is unlikely to mark a turning point for the yen, but we see scope for a short squeeze that pushes the yen at least temporarily higher against the US dollar this week," said Homin Lee, a senior macro strategist at Lombard Odier Singapore. "It can't be sustained indefinitely against a backdrop of fiscal worries and gradual BOJ rate hikes." The BOJ's next policy meeting will be watched for whether Ueda follows through on his hawkish signal, with markets pricing the path of further hikes against the risk of renewed yen weakness.

This article is for informational purposes only and does not constitute investment advice.