Japan confirms rare joint yen intervention with US, warns of more action

Japan and the United States conducted a coordinated yen-buying intervention and will not hesitate to take further action, Japan’s Finance Ministry said on Monday, confirming a rare bilateral move to halt the yen’s slide to fresh 40-year lows.

The announcement underscores both countries’ resolve to prevent a sell-off in the yen and Japanese government bonds from causing global spillovers, such as adding upward pressure on already rising U.S. Treasury yields, analysts say.

The joint intervention is the first since 2011’s coordinated action to weaken the yen after the devastating earthquake in eastern Japan.

In its statement, Japan’s Finance Ministry said Friday’s yen-buying intervention with the U.S. Treasury Department “countered excessive volatility and disorderly movements in the Japanese yen in recent months”.

“The Japanese Ministry of Finance remains attentive and in close communication with our counterparts at the U.S. Treasury,” it added. “We will not hesitate to conduct further joint intervention.”

Preceding the announcement, U.S. President Donald Trump said on Sunday that the United States was helping Japan to prop up the yen as a sign of friendship and to help the world economy.

“They have a weakening yen, and they wanted a little bit of help. And we’re always there for Japan,” Trump said in response to a reporter’s query why the U.S. is helping to support the yen.

The dollar suddenly dropped against the yen on Monday, reversing gains it made earlier in the session after the confirmation from the U.S. and Japan that they intervened in the currency market. The dollar fell 0.6% against the yen to an intraday low of 156.50 in the Asian morning.

“The joint intervention is the culmination of Japan’s alliance with the United States,” Japan’s top currency diplomat Atsushi Mimura told reporters on Monday.

“We will continue to align [currency policy] with the Bank of Japan’s monetary policy,” he said, suggesting the government will work hand in hand with the BOJ in arresting yen falls.

U.S. Treasury Secretary Scott Bessent also confirmed Friday’s effort, adding Washington “will not hesitate to participate in further joint intervention.”

“We strongly support Japan’s decisive market and monetary steps to correct the substantial undervaluation of the yen,” Bessent said in a separate statement on X, repeating his calls for further interest rate hikes by the Bank of Japan.

The remarks put the spotlight on the BOJ, which last week kept rates on hold but signaled scope for a rate hike as soon as its next policy meeting in September.

Japan has been struggling to curb a relentless drop in the yen that pushes up import prices and stokes broader inflation, hitting households’ wallets and Prime Minister Sanae Takaichi’s public approval ratings.

Tokyo’s solo intervention conducted between late April and early May caused only a brief yen rebound. The BOJ’s June rate hike to a 31-year high of 1% also gave the struggling currency little lasting boost.

Before Friday’s confirmed joint intervention with the U.S., Japan may have sold as much as $58.97 billion to buy yen when it intervened in New York markets on Thursday, BOJ data suggested.

Analysts doubt whether the latest round of action could counter structural factors driving down the yen, such as the rising cost of fuel from the Middle East conflict and the still wide Japan-U.S. interest rate differentials.

“The announcement effect of joint intervention is much bigger than solo action by Japan,” though the yen fell after the announcement as it was largely within expectations, said Tsuyoshi Ueno, a senior economist at NLI Research Institute.

“The fundamentals driving yen weakness haven’t changed, so we likely won’t see one-sided yen rises from this intervention.”