Global Oil Supply Routes

The Strait of Hormuz has been reclosed as of 18 April 2026 — within hours of a brief diplomatic opening on 17 April. Iran shut the strait again citing the US maintaining a naval blockade on Iranian ports in breach of ceasefire terms. The closure is part of the wider US-Israel-Iran conflict that began in late February 2026. Traffic through the strait is down approximately 90% from normal: 19 transits recorded on 15 April versus the pre-crisis norm of ~138 per day. Over 230 loaded oil tankers are reported queued in the Gulf.

The 17 April ceasefire deal collapsed within hours when the US refused to lift its blockade on Iranian ports. Iran stated that Hormuz will remain under "strict management" of its armed forces until the US restores freedom of navigation for Iranian vessels. The US blockade has so far deterred over 13 merchant ships from transiting. The IRGC has called the US blockade "acts of piracy." Diplomatic back-channel talks are reported ongoing. The Red Sea/Suez route remains independently disrupted by Houthi attacks. Both primary Gulf-to-Europe export corridors are now closed simultaneously.

The southern entrance to the Red Sea remains actively disrupted by Houthi attacks since November 2023. Around 4.5 mb/d of oil and products normally transits this route; daily traffic through Bab-el-Mandeb and Suez Canal remains far below pre-attack levels. With Hormuz also reclosed as of 18 April 2026, both primary Gulf export corridors are simultaneously disrupted.

Operation Prosperity Guardian has not restored commercial transit confidence. Insurance premiums for Red Sea passage remain prohibitive. The Houthi threat is geopolitically linked to the broader US-Iran-Israel conflict; Hormuz reclosure (18 April) and Bab-el-Mandeb disruption now overlap, placing the entire Gulf-to-Europe oil corridor under simultaneous constraint. Red Sea normalisation requires a separate Houthi ceasefire.

Chinese naval and coast guard vessels have established a blockade around Scarborough Shoal, disrupting Philippine maritime access and raising the risk of broader interference with commercial tanker traffic through the South China Sea. The sea lane carries approximately 3.4 mb/d of oil — primarily Middle Eastern crude transiting to China, Japan, and South Korea — along with significant LNG volumes. While the blockade is currently focused on the Shoal itself rather than the main tanker lanes, the escalation introduces material operational risk to one of the world's busiest energy corridors.

The Scarborough Shoal has been a flashpoint in China-Philippines tensions since China effectively seized control of the feature in 2012. The current blockade escalates well beyond previous stand-offs and has drawn US statements under the Mutual Defense Treaty with the Philippines. A full closure of the broader South China Sea to commercial traffic — while not the current situation — would represent one of the most severe supply shocks in modern history, affecting roughly a third of global seaborne oil trade. The situation is being monitored by the IEA and has been noted in recent IMF growth revisions.

The Suez Canal carries around 5.5 mb/d of oil and petroleum products plus significant LNG volumes. Red Sea avoidance by commercial tankers has kept Canal transit volumes far below pre-disruption levels since late 2023. Cape of Good Hope diversion remains the operating norm for Gulf-to-Europe cargoes. Hormuz has been reclosed as of 18 April 2026, meaning both primary Gulf-to-Europe export corridors are now simultaneously blocked.

The Sumed pipeline can carry approximately 2.5 mb/d of crude as a bypass but not refined products. EU member states have largely adapted sourcing to Atlantic Basin suppliers, but at sustained higher cost. A Houthi ceasefire remains the necessary condition for Red Sea/Suez recovery.

The only maritime access to the Baltic Sea. Pre-sanctions, around 3 mb/d of Russian crude and products from Baltic ports (Primorsk, Ust-Luga) transited this route. Post-2022 sanctions have reduced Russian flows but shadow fleet tankers continue to carry Russian oil, raising insurance and environmental concerns.

Denmark and Sweden are both NATO members and have shown willingness to scrutinise shadow fleet tanker transits. The EU has progressively tightened enforcement of price cap rules on Russian oil transiting these waters. Several shadow fleet vessels have been detained or refused port access in the region.

The Bosphorus and Dardanelles control Black Sea access to the Mediterranean. Around 2.4 mb/d passes through — primarily Kazakhstani crude via the CPC pipeline and residual Russian Black Sea exports. Turkey has periodically restricted passage, citing insurance requirements linked to Western price cap enforcement on Russian oil.

Turkey operates transit rights under the 1936 Montreux Convention. The EU price cap on Russian oil has created ongoing legal and commercial friction around insurance requirements for vessels. Turkey has resisted pressure to fully enforce EU-aligned restrictions, creating a persistent compliance gap.

The Amsterdam-Rotterdam-Antwerp (ARA) complex is Europe's largest refining and oil storage hub, handling around 4 mb/d of crude and products. It acts as the primary pricing and distribution point for Northwest European fuel markets. Rotterdam alone is the world's largest port by cargo volume. Note: shipping around Antwerp was partially halted on 10 April 2026 following an oil spill; this is an operational incident under containment rather than a structural supply route disruption.

ARA commercial storage acts as a buffer for European supply disruptions. Tanker arrivals at Rotterdam are a leading indicator of fuel availability. ARA stock levels are published weekly by Insights Global and monitored closely by energy traders. In the current environment, ARA stock drawdown is the key metric to watch for early signs of downstream tightness.