US-Japan yen intervention targets 155.20 as bond fears mount

The coordinated US-Japan yen intervention that pushed USD/JPY to 155.20, its lowest since May 6, reflects Washington's fear that Japan will dump its $1.14 trillion of Treasuries, not just currency stabilization.

"Intervention only has a temporary effect in slowing currency moves. Faster rate hikes are probably needed to put a lasting floor on the yen," said Naomi Muguruma, chief bond strategist at Mitsubishi UFJ Morgan Stanley Securities.

The pair has fallen more than 4 percent from its year-to-date high of 163.97, with the dollar sliding 0.6 percent against the yen to an intraday low of 156.50 during Asian trading before touching 155.45. Tokyo confirmed it conducted yen-buying intervention with Washington on Friday, a day after the Bank of Japan spent about 8.45 trillion yen, or $52.8 billion, in its own operation. The US Treasury, through the Federal Reserve Bank of New York, converted euro holdings into dollars via Morgan Stanley and Goldman Sachs, according to the Financial Times. The dollar index slipped 0.47 percent to 99.4474.

The stakes extend beyond the currency. Japan remains the largest foreign holder of US public debt at $1.14 trillion, down from a $1.24 trillion peak in February, and Washington fears further selling would push yields higher as the 30-year Treasury already trades near a 19-year high of 5.28 percent. With US public debt approaching $40 trillion and deficits expected to hit $2 trillion, the intervention is a bid to keep Japan from following China, which has cut its holdings to $659 billion from over $1.3 trillion in 2013.

A September rate hike looks near-given

The intervention has shifted focus to the Bank of Japan's next move. Both the Fed and BoJ left rates unchanged last week, but Governor Kazuo Ueda delivered the central bank's most hawkish communication to date, emphasizing vigilance "more than ever" against upside price risks — read by analysts as all but confirming a September hike. Markets now see the September 17-18 meeting as live, with Muguruma calling a hike "a done deal."

The BoJ raised rates to a 31-year high of 1 percent in June, but with real borrowing costs deeply negative, the move failed to give a lasting boost to the yen. US Treasury Secretary Scott Bessent, whose "to do" list at a Friday cabinet meeting read "Buy Japanese Yen (JPY) $5-10 bil," has repeatedly called for faster BoJ hikes and said he would meet Ueda at a G20 finance leaders' meeting in late August. Japan's top currency diplomat, Atsushi Mimura, said the government will align its currency policy with the BoJ's monetary policy, signaling the chance of a near-term hike.

Trade surplus adds to the pressure

President Donald Trump's focus on trade deficits gives Washington another reason to back a stronger yen. Japan's trade surplus with the US jumped to over $47 billion, driven by vehicles and machinery, and a weaker yen has helped offset the impact of Trump's tariffs. A stronger yen would boost US exports and, Trump hopes, help Prime Minister Sanae Takaichi bring inflation down.

Still, the effect of intervention is likely to be short-lived given the interest-rate differential between the US and Japan. Analysts predict the Fed will hike this year, and unless the BoJ follows, the yen will remain under pressure. The last time Tokyo intervened in April, the pair rebounded before resuming its climb — a pattern that suggests 155.20 may not hold without a September rate hike to back it up.

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