BOJ to Hike Rate in July Hike as Iran War Turns Oil Shock Into a Policy Test for Japan

The Bank of Japan is moving closer to another interest-rate increase, with former board member Seiji Adachi warning that the central bank risks falling behind the curve as the Iran war drives a fresh oil shock through Japan’s import-dependent economy.

In remarks that sharpen expectations for further monetary tightening, Adachi said the BOJ will likely raise rates by July, and possibly as early as April or June, as rising crude prices and supply disruptions intensify inflation risks.

“The BOJ will probably raise rates again in April, June or July,” Adachi told Reuters, adding that “with the Middle East conflict, the risk of the BOJ falling behind the curve in dealing with inflation has heightened somewhat.”

That assessment is particularly important because it captures the increasingly difficult position facing the BOJ: contain imported inflation without derailing a still-fragile domestic recovery.

Japan’s economy is uniquely exposed to the conflict. As one of the world’s largest importers of crude oil and liquefied natural gas, Japan is highly vulnerable to disruptions in the Strait of Hormuz, through which roughly a fifth of global oil and gas flows pass. With the conflict constraining supply and keeping crude prices elevated, the country’s import bill is rising sharply, feeding directly into consumer prices, transport costs, and industrial margins.

This is where Adachi’s warning becomes more consequential. Unlike the United States or some European economies, Japan’s inflation dynamic remains heavily influenced by imported costs and the yen’s exchange rate.

The latest Tankan survey already showed five-year corporate inflation expectations rising to 2.5%, above the BOJ’s long-standing 2% target. That is a critical signal because it suggests businesses increasingly expect inflation to persist, not fade.

Adachi noted this shift in explicit terms. “Underlying inflation has already hit the central bank’s 2% target,” he said.

For years, the BOJ struggled to sustainably lift inflation expectations after decades of deflation and weak wage growth. Now, the risk has reversed: inflation may begin to embed itself more firmly in the economy, especially if the oil shock proves prolonged.

Adachi’s view is that rates need to move closer to neutral territory.

“It’s better for the BOJ to raise rates to levels deemed neutral to the economy as soon as possible,” he said, adding that Japan’s neutral rate “likely stood somewhere around 1.25%.”

That implies there may be room for two additional 25-basis-point hikes this year, taking the policy rate from 0.75% to 1.25%. Such a move would mark one of the most significant tightening phases in Japan’s monetary history, especially after decades of ultra-loose policy and negative rates.

Still, the uncertainty surrounds the timing. Adachi said the probability of an April move is “50-50,” acknowledging that policymakers must weigh inflation risks against war-driven market volatility and the broader economic fallout.

“But whether it hikes in April would be a tough call, as doing so would mean pulling the trigger when the economic impact of the war remains unclear,” he said.

This captures the BOJ’s core dilemma. Raise too slowly, and imported inflation worsens while the yen remains under pressure. Raise too quickly, and the central bank risks tightening into an economy where consumption and corporate investment are still recovering.

The political backdrop complicates matters further. Adachi noted that the government may not be fully aligned with aggressive near-term tightening.

“The fact dovish Prime Minister Sanae Takaichi appointed two reflationists to join the BOJ board is a sign the administration is opposed to further near-term rate hikes,” he said.

That is a crucial institutional insight because higher rates are expected to increase borrowing costs for businesses at a time when Tokyo is pushing investment into semiconductors, advanced manufacturing, defense, and clean energy.

“Rate hikes would push up the cost of corporate borrowing. That runs counter to the administration’s push to boost investment in growth areas,” Adachi added.

There is also a global market dimension that makes this story larger than Japan. A BOJ rate hike could strengthen the yen and trigger some repatriation of Japanese capital currently invested overseas, particularly in U.S. Treasuries and global equities.

That matters because Japanese institutions remain among the largest foreign holders of U.S. government debt. Any material shift in capital flows could place upward pressure on global bond yields and tighten financial conditions beyond Asia.

If the war evolves into a prolonged energy shock, Adachi suggested the BOJ may need to move faster.

“If the Middle East war turns into a protracted conflict that triggers a more than year-long oil shock, the BOJ may need to hike rates at a faster pace to push real borrowing costs out of negative territory,” he said.

“We’re not there yet,” he added. “But depending on how the conflict unfolds, the BOJ will face a very tough decision, sandwiched between rising inflation and low growth.”

That final point is perhaps the most important. The Iran war is no longer just a geopolitical or energy-market event. It is now directly influencing the policy trajectory of one of the world’s most systemically important central banks.