European gas benchmarks moved in violent steps once the U.S.-Israeli war on Iran began on February 28, 2026. By the following Monday, front-month TTF futures had jumped roughly a quarter in a single session, per WSJ live coverage. The move compounded from there. By March 3, TTF had surged as much as 48%, touching its highest level since 2023, with the acceleration tied to uncertainty over a halt in Qatari LNG loadings — a disruption WSJ called "the biggest threat to world gas markets since Russia invaded Ukraine" (WSJ). Separate reporting the same day put the intraday surge at 50%, to 48 euros per megawatt-hour, with UK NBP futures up 41% to 115 pence per therm (Fool.com.au). By the close of that trading week, TTF had rallied 67%, its steepest weekly gain since the 2022 energy crisis (Bloomberg).

The mechanism is the Strait of Hormuz. The U.S. Congressional Research Service published an analysis on March 11 assessing how the conflict threatens oil, gas and broader energy flows through the chokepoint (CRS). The U.S. subsequently launched retaliatory strikes on dozens of Iranian targets following attacks on shipping in the Strait, per CBS News. For a market still carrying structural scar tissue from the loss of Russian pipeline gas, any credible threat to Qatari LNG cargoes transiting Hormuz — Qatar being Europe's most important marginal LNG supplier since 2022 — reprices the entire curve almost instantly. That's the transmission channel traders were pricing on March 3: not a confirmed cutoff, but the probability-weighted cost of one.

Policymakers moved quickly. By March 11, the EU was weighing a suite of measures to blunt the cost shock, including a gas price cap (Bloomberg). The bloc's prior experience with the 2022 Market Correction Mechanism — which was never triggered and drew criticism for its restrictive activation thresholds — sets a low bar for how quickly a fresh cap could actually bind liquidity or bid-ask spreads on TTF if implemented under similar conditions. By March 26, Reuters reported benchmark European gas had risen more than 60% since the conflict's start, above 50 €/MWh, and that Brussels was scaling back near-term climate targets explicitly to manage the energy shock (Reuters). Five days earlier, HSBC had revised its 2026 European gas forecast 40% higher than its pre-war base case, with prices expected to stay elevated through 2027 (Bloomberg) — a call that, if it holds, has direct implications for utility hedging books and industrial power-purchase agreements priced off multi-year TTF strips.

The picture softened by late spring. WSJ reported on May 25 that European gas prices fell 5% on optimism tied to U.S.-Iran talks, and a U.S.-Iran interim agreement was in place by mid-June with consequences flagged for the maritime and tanker-insurance sectors (Holland & Knight). But de-escalation has not meant reversion. Reuters' June 17 assessment is the operative benchmark now: average European gas prices remained roughly 31% higher — about 10 €/MWh above pre-conflict levels — nearly four months after the war began, even as the acute Hormuz shock had receded from headlines (Reuters). That 31% figure, not the peak-week 67% weekly gain or the March 26 60%-since-conflict-start reading, is the one that matters for anyone marking a curve today — it's the most recently reported, and it captures what's actually stuck rather than what merely spiked.

The gap between the March peaks and the June baseline tells its own story about market memory. A 67% weekly surge is a liquidity event — forced short-covering, margin calls, algorithmic momentum chasing a geopolitical headline. A 31% sustained elevation four months on is a repricing of risk premium: the market's residual assessment that Hormuz-transiting LNG and the broader Gulf supply chain carry a structurally higher probability of disruption than it assumed in January 2026. For treasurers and hedgers, that distinction is the whole ballgame — a spike fades from the curve; a repriced risk premium gets carried into forward strips, industrial cost pass-through, and, eventually, headline inflation prints across the eurozone and UK. HSBC's through-2027 call was a bet on the latter interpretation holding. The June data suggests it was, at minimum, directionally right, even if the magnitude has moderated from the March extremes.