Japanese government bond (JGB) yields experienced a significant drop, with the 10-year JGB yield falling from 2.896% to 2.842%, marking its largest single-day rally since July 14. This movement followed an unexpected announcement by the U.S. Treasury Department to more than double its repurchase operations for 10-year to 30-year notes to $4 billion per session. This action was a direct response to a multi-day selloff in global government bond markets that had driven long-term borrowing costs to multi-decade highs, including a 30-year peak of 2.945% for the 10-year JGB earlier in the week.
The U.S. Treasury's expanded buybacks were intended to provide a backstop for off-the-run securities and calm market anxieties related to widening G10 fiscal deficits and heightened energy-supply risks from the Persian Gulf. This intervention led to a global pull back in sovereign yields, with Asian sovereigns, particularly JGBs, anchoring the relief rally. U.S. 10-year Treasury yields also fell to 4.647% and 30-year yields dropped to 5.198% in response to the news.
Despite the immediate relief, Japanese market participants remain cautious. Analysts noted that concerns persist regarding potential Bank of Japan rate increases, possibly as soon as September, and ongoing fiscal uncertainty tied to consumption tax proposals. A widening July trade deficit, exacerbated by record crude imports, further constrains expectations for a sustained rally in Japanese bonds. Short-dated European yields, however, continued to rise due to expectations of further central bank restraint and elevated Brent crude prices above $91, keeping the term premium high.
Experts suggest that Japan has limited options to combat a bond rout, with sporadic cuts to bond issuance or emergency central bank buying offering only temporary solutions. The 10-year JGB yield was on the verge of hitting 3% for the first time since the mid-1990s, driven by stubborn inflation and a loose fiscal stance. If the 10-year JGB yield exceeds 3%, which was the government's budget assumption, debt-servicing costs could surge past the currently allocated 31 trillion yen ($195 billion), undermining Prime Minister Sanae Takaichi's spending agenda. The finance ministry's baseline estimate projects debt-servicing costs to rise to 41 trillion yen by fiscal 2029 if the 10-year yield climbs to 3.6%.
