Iran War Chokes Hormuz, Diverts Diesel Cargoes and Tightens Global Middle Distillate Supply

Escalating military conflict involving Iran and the effective closure of the Strait of Hormuz have triggered a sharp dislocation in global refined product flows, with diesel and gasoil markets tightening rapidly. Cargoes originally bound for Europe from US refineries are being resold mid-voyage and diverted to Africa and Asia, where gasoil prices have surged to steep premiums over European benchmarks, intensifying competition for barrels and raising freight and risk premia across middle distillate markets.

While no acute physical shortage has yet materialised in Europe, the underlying balance for diesel is becoming increasingly fragile, with structurally import-dependent markets now exposed to both Middle East supply losses and aggressive Asian buying.

Introduction

Since late February 2026, joint US–Israeli strikes on Iran and retaliatory Iranian actions have severely disrupted oil and gas flows through the Strait of Hormuz, a chokepoint that normally carries around 20% of global seaborne oil and liquefied natural gas (LNG). Multiple attacks on energy infrastructure, including facilities at South Pars and Kharg Island, and Iran’s effective blockade of the strait have stranded millions of barrels per day of crude and products.

This shock is now rippling through refined product markets. Europe, which relies heavily on imports of diesel and gasoil from the US Gulf Coast, the Middle East and Asia, is seeing key supply streams curtailed or rerouted. As Asian buyers, themselves hit by lost Middle Eastern supply, bid aggressively for spot cargoes, several US diesel tankers originally destined for European ports have changed course toward African hubs as staging points for Asia, tightening availability in the Atlantic Basin.

🌍 Immediate Market Impact

The effective closure and partial, toll-based reopening of the Strait of Hormuz have cut or constrained flows of crude and refined products from Iran, Iraq, Kuwait, Saudi Arabia and the UAE, pushing global crude benchmarks sharply higher and adding a sizeable risk premium. Brent has traded well above US$100 per barrel at points in March, with record intraday volatility driven by shifting war headlines.

For diesel, the loss of Middle Eastern barrels and elevated shipping risk are amplifying tightness. Asia, which receives the bulk of Hormuz-transiting oil and LNG, faces particularly acute shortages and has driven gasoil prices on the Singapore benchmark to a reported premium of around US$200–230 per tonne over European ICE gasoil. This spread is large enough to justify redirecting US Gulf Coast diesel cargoes mid-Atlantic toward Africa and then on to Asia, even as freight and insurance rates spike.

📦 Supply Chain Disruptions

Shipping disruptions around Hormuz, including attacks on commercial vessels and new Iranian transit tolls, have significantly reduced tanker traffic and delayed loadings from Gulf export terminals. Some Saudi and Emirati volumes are being rerouted via alternative pipelines and ports, but capacity is limited relative to pre-war flows.

At the same time, tight tanker availability and elevated war-risk insurance are driving up freight costs globally, complicating long-haul diesel trade from the US Gulf to Europe and from remaining Middle Eastern and Asian hubs to deficit regions. LNG freight rates and broader energy shipping costs in the Atlantic basin have effectively doubled in recent weeks, underscoring the strain on maritime logistics.

European refiners are struggling to offset lost inflows of both crude and middle distillate feedstocks, while Asian refiners that previously exported surplus diesel are facing feedstock shortages due to Gulf crude and condensate disruptions. This dual constraint—on both crude supply and refined product exports—is at the core of the emerging diesel squeeze.

📊 Commodities Potentially Affected

• Diesel and Gasoil – Directly hit by disrupted Gulf exports, redirected US cargoes, and surging Asian demand; European benchmarks face upside price risk and widening backwardation.
• Jet Fuel/Kerosene – Shares refinery streams with diesel; yields are being optimised toward diesel, potentially tightening aviation fuel supply and lifting crack spreads in key hubs.
• Fuel Oil and Marine Gas Oil (MGO) – Higher middle distillate prices and bunker fuel logistics issues around alternative routes (e.g., around the Cape of Good Hope) may raise shipping costs for agricultural commodities.
• LNG and LPG – Although not the focus of this report, disrupted Hormuz traffic and Qatar’s curtailed LNG exports are lifting gas prices in Europe and Asia, increasing energy and fertiliser production costs.
• Fertilisers and Energy-Intensive Agro-Inputs – Higher gas and diesel prices increase production and transport costs for nitrogen fertilisers, agrochemicals and farm diesel, affecting crop margins globally.

🌎 Regional Trade Implications

Europe faces the sharpest immediate risk on diesel because of its structural shortfall and reliance on imports from the US Gulf, the Middle East and Asia. With Gulf and Asian supply constrained and US cargoes being diverted, European importers may be forced to pay higher premiums to retain volumes, draw down stocks, and potentially reduce non-essential diesel use if tightness persists.

Asian importers, especially in South and Southeast Asia, are leveraging higher regional gasoil prices to attract Atlantic Basin supply, but at the cost of substantially higher energy import bills and increased exposure to freight and security risk. Major consuming economies such as India and China are also tapping strategic stocks and exploring alternative crude routes, including pipelines that bypass Hormuz.

Producers with pipeline or non-Hormuz export options—such as Russia, some North Sea producers, and to a degree Saudi Arabia and the UAE via bypass infrastructure—stand to capture market share and higher crack spreads. However, constraints on refining capacity and sanctions-related frictions limit how far these alternative flows can compensate for Gulf losses in the near term.

🧭 Market Outlook

In the short term, diesel and gasoil markets are likely to remain exceptionally volatile, with prompt prices and cracks reacting to any signals on the duration of Hormuz disruption, further attacks on infrastructure, or coordinated stock releases by consuming nations. The redirection of US Gulf Coast cargoes away from Europe toward Africa and Asia highlights how quickly arbitrage flows can shift in response to regional price dislocations.

If the conflict and shipping constraints extend into April and beyond, traders should prepare for sustained high middle distillate cracks, elevated freight and insurance costs, and periodic regional shortages, particularly in Europe and parts of Asia. Monitoring tanker traffic patterns, announced refinery run adjustments, and policy moves such as temporary product export restrictions or fuel tax interventions will be critical for positioning.

CMB Market Insight

The Iran war and the effective throttling of the Strait of Hormuz have moved from being a crude oil story to a refined product and logistics crisis, with diesel at the centre. The combination of lost Gulf supply, disrupted Asian exports, and the diversion of US cargoes is tightening global middle distillate balances just as many importing regions enter key agricultural and industrial demand seasons.

For agricultural commodity traders and the wider food supply chain, the key strategic takeaway is that energy-related input costs and transport expenses are likely to remain elevated and volatile. Hedging strategies that integrate fuel, freight and key agricultural exposures, alongside close tracking of evolving trade flows between the Atlantic and Pacific basins, will be essential to manage margin risk in the coming weeks.