How the Strait of Hormuz Crisis Is Forcing the ECB's First Rate Hike in Three Years

In early 2026, the eruption of a major military conflict involving Iran led to the effective closure of the Strait of Hormuz—a narrow waterway through which roughly one-fifth of the world's oil trade passes. This single event ruptured the European Central Bank's economic playbook. After holding its key deposit rate steady at 2.0% since June 2025, the ECB is now preparing to raise rates for the first time in nearly three years, navigating a treacherous crossroads where a supply-driven inflation surge meets a rapidly deteriorating economic outlook.

The interconnected crisis is the result of three colliding forces: an external energy-price shock, persistent inflation overshooting the 2% target, and deep structural vulnerabilities left over from Europe's previous energy crisis.

The Shock Heard Around the World

The immediate trigger was the closure of the Strait of Hormuz, which sent oil and natural gas prices soaring. The European Union estimated that gas prices spiked by 70% and oil by roughly 50%, adding a €13 billion bill for fossil fuel imports almost overnight. Brent crude prices, which hovered around $70 per barrel before the conflict, jumped to approximately $119 per barrel.

This external shock hit the eurozone hard. Unlike previous global events, this wasn't a risk—it was an immediate, physical supply disruption. The ECB's March 2026 staff macroeconomic projections painted a grim picture: Harmonized Index of Consumer Prices (HICP) inflation was forecast to surge to 3.1% in the second quarter of 2026, driven by a spike in energy costs. The baseline scenario saw average headline inflation reaching 2.6% for the full year, a sharp upward revision from the 1.9% forecasted just months earlier in December 2025.

By late spring, the data on the ground confirmed the worst fears. Annual inflation in the eurozone rose to 3.0% in April, then accelerated to 3.2% in May—the third consecutive month above the ECB's target and the highest level in over two years. Across the bloc's "Big Four" economies, higher energy costs, particularly for natural gas, were the primary driver of headline price increases.

When Higher Prices Mean Slower Growth

The ECB’s dilemma is that the exact same force pushing up inflation is simultaneously crushing economic growth—a classic stagflationary dynamic. Higher energy bills erode consumers' purchasing power, leaving them with less money to spend on other goods and services. Simultaneously, soaring geopolitical uncertainty chips away at business confidence and investment.

Consequently, growth forecasts have been slashed. Before the conflict, the Eurosystem's December 2025 projections forecasted real GDP growth of 1.2% for 2026. By March 2026, the ECB had cut this figure to 0.9%. The European Commission’s Spring 2026 Economic Forecast echoed this pessimism, downgrading its growth outlook for the bloc to 1.1%, with heavy cuts for major economies like Germany, whose 2026 growth forecast was halved to 0.6% from a previous estimate of 1.2%.

The Conference Board maintained that euro area growth would likely slow to just 1.0% in 2026, while even more bullish voices like Barclays acknowledged that their "nowcasting" model pointed to a quarterly GDP contraction in the first three months of the year.

A Structural Weakness Exposed

The intensity of the pain stems from Europe's enduring dependence on imported energy. The 2022 energy crisis forced the bloc to scramble for alternatives to Russian gas, but by early 2026, the eurozone remained highly exposed to global price swings. The Strait of Hormuz crisis turned that vulnerability from a latent risk into an acute and costly reality.

Analysts and institutions have framed this shock not as a fleeting disruption but as a structural challenge. A Deutsche Bank Wealth Management note warned that the surge in energy prices represented "not just a temporary market incident – it represents a structural increase that could lead to stagflation in key European economies." A research note from the Allianz group warned that a prolonged conflict could delay monetary easing cycles by repricing inflation expectations more forcefully across the yield curve.

This structural vulnerability means the ECB can't simply dismiss the inflation surge as "transitory" and wait it out. Even if hostilities were to end quickly, the experience of 2022 has taught policymakers that energy-driven inflation can embed itself into the broader economy through second-round effects on wages and broader service prices. The ECB’s April meeting minutes revealed that a number of members already viewed the decision to keep rates unchanged as a "close call" and would have supported a hike, citing the supply shock as proving more persistent than previously expected.

The Inevitable Hike and an Uncertain Future

The trajectory toward a rate hike moved from speculation to near-certainty within months of the conflict's onset. By late April, a Reuters poll found that just over half of economists expected the ECB to hold in April but deliver a quarter-point hike in June. By late May, ECB Executive Board member Isabel Schnabel publicly stated that a June rate increase was necessary to combat the war-driven energy inflation, with eurozone inflation reaching a full percentage point above target.

The decision is not just about fighting price increases; it's about managing credibility. The International Monetary Fund weighed in, projecting a cumulative 50-basis-point increase in the policy rate by the end of 2026 to maintain a broadly neutral stance, even as it acknowledged the high degree of uncertainty surrounding the growth outlook.

This has set the stage for a policy paradox. The ECB is effectively preparing to raise the cost of borrowing for businesses and households at a moment when the risk of a recession is rising. The bank itself acknowledges the difficult balancing act, with one internal economic bulletin warning that the war has made the outlook "significantly more uncertain, creating upside risks for inflation and downside risks for economic growth."

The crucial unknown is what happens after a likely June hike. The path beyond is unclear because the key variable—the duration and intensity of the Strait of Hormuz disruption—remains unknowable. As JP Morgan Asset Management noted, higher inflation and lower growth can be expected across most economies, but the final impact depends on a complex calculus of conflict duration, the extent of second-round effects, and institutional policy responses. The eurozone stands at a crossroads where a wrong step could either entrench inflation or extinguish an already-fragile recovery, making this the most perilous moment for European monetary policy since the bloc's sovereign debt crisis.