JGBs fall tracking US Treasurys as VIX jumps 4.8% on Iran

Japanese government bonds declined in Wednesday morning Tokyo trading, tracking an overnight selloff in U.S. Treasurys as renewed military conflict between the United States and Iran pushed the Cboe Volatility Index up 4.8% to 16.90 and crude oil above $74 a barrel.

MarketWatch data shows the Dow Jones Industrial Average fell 1.09% to 52,348.39 and the S&P 500 declined 0.28% to 7,482.71, while gold rose 0.28% to $4,093.80 an ounce as investors rotated into haven assets. The selloff in U.S. government bonds accelerated after President Donald Trump declared the U.S.-Iran ceasefire over and American forces struck Kharg Island, which handles the majority of Iran's oil exports.

The Strait of Hormuz is back under "full-conflict conditions," according to analysts cited by MarketWatch, raising concerns about disruptions to the waterway that handles about 21% of global oil trade. Oil prices extended gains in after-hours trading as U.S. forces conducted additional strikes on Iran, with WTI crude settling at $74.19 a barrel, up 0.91% on the day.

The escalation threatens to revive inflation pressures through higher energy costs, potentially complicating the Federal Reserve's rate path. Polymarket data cited by MarketWatch shows traders pricing in a 79% probability of no Fed rate cuts through the remainder of 2026, reflecting the market's assessment that higher oil prices could keep inflation above the central bank's 2% target.

The JGB decline extends a period of heightened sensitivity in Japanese fixed-income markets as investors weigh the Bank of Japan's normalization trajectory against global headwinds. Japanese institutional investors are among the largest foreign holders of U.S. government debt, creating a direct transmission channel between U.S. Treasury moves and JGB prices. The BoJ has been gradually moving away from its ultra-loose monetary policy stance, and a sustained rise in global yields could influence the pace of its normalization.

The broader risk-off move also weighed on Asian equity markets, with the Dow's 576-point decline setting a negative tone for regional trading. The dollar index stood at 100.97, down from the previous session, while haven currencies including the yen drew bids. The simultaneous decline in both equities and bonds — a break from the typical negative correlation — signaled that the move was driven by a geopolitical risk premium rather than growth expectations.

The current conflict, involving strikes on Iranian energy infrastructure, directly threatens global energy supply routes through the Strait of Hormuz. Higher oil prices could feed through to consumer prices, potentially keeping central banks on hold for longer than markets had anticipated. The next key data point for markets will be U.S. inflation figures, which will show whether the initial pass-through from higher energy costs has begun to materialize.

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