Full Breakdown
Strait of Hormuz Closure Disrupts Global Oil Flows Amid Iran Conflict
6/5/2026, 8:59:53 AM
Key Developments in the Hormuz Blockade
Since the U.S.–Israeli strikes on Iran on 28 February 2026, Iran has kept the Strait of Hormuz effectively closed. Satellite-based tracking firm Kpler recorded only a handful of vessels crossing the waterway. Four Iranian-flagged tankers—Hilda I, Amber, Silvia 1 and Happiness I—transited on 1 June, the first such movement since 15 April. The same firm estimates that between 1 March and 19 May, 895 tankers attempted the passage, but 358 of them disabled their Automatic Identification System (AIS) to “go dark.”
Background and Context of the Conflict
The blockade follows Iran’s retaliation to the February air campaign launched by the United States and Israel. Tehran has linked any reopening to the lifting of the U.S. naval blockade of Iranian ports and to the removal of sanctions on the newly created Persian Gulf Strait Authority (PGSA). In parallel, the United States has sanctioned the PGSA and warned of secondary sanctions against firms paying Iran’s reported tolls of up to $2 million per transit.
Shipping Patterns and Dark-Fleet Tactics
Analysts at Vortexa note that the proportion of “dark” outbound tankers rose from 37 % in the first month of the war to 65 % in May. Lloyd’s List Intelligence reports that nearly 40 ships previously stranded in the Gulf have exited over the past three weeks after coordinating with the U.S. Navy’s Naval Cooperation and Guidance for Shipping (NCGS) group in Bahrain. However, the U.S. Navy does not escort commercial vessels; it merely provides “limited assurances” of safe passage.
Impact on Global Oil Markets and Inventories
The disruption has trimmed daily global oil flow through Hormuz from roughly 20 million bbl to less than 5 million bbl. Brent futures traded between $94 and $98 per barrel in early June, while U.S. West Texas Intermediate hovered near $95. U.S. commercial crude inventories fell by 8 million bbl in the week to 29 May, and the Strategic Petroleum Reserve (SPR) dropped to ? 357 million bbl, a decline of about 50 million bbl since the war’s start.
Official Statements and Policy Responses
- Sultan al-Jaber, CEO of ADNOC, warned that “if global demand creeps back up and the Hormuz crisis continues, global oil prices could resume their upward march as early as August.”
- Jarrod Agen, director of the White House National Energy Dominance Council, asserted that the United States “does not have a supply problem, obviously.”
- Philippe Khoury, EVP of Sales & Trading at ADNOC, said the UAE is evaluating a multi-fuel pipeline to bypass Hormuz, complementing its existing 1.5 million bbl-per-day crude line to Fujairah.
Criticism and Opposition
U.S. sanctions on the PGSA have drawn criticism from shipping firms that argue the measures “undermine commercial freedom” and force operators to rely on risky “shadow-fleet” routes. Vortexa cautioned that “AIS-off behaviour is becoming an accepted operating protocol, not an exceptional measure,” highlighting the growing normalization of illicit navigation tactics.
Conflicting Reports and Gaps
Sources differ on the average daily transits: Kpler cites 7–10 vessels per day, while Bloomberg reports “significantly below pre-conflict levels” without a precise figure. Additionally, the U.S. Navy’s role is described as “coordinating with shippers” (Lloyd’s List) versus “not escorting commercial ships” (U.S. defense official).
Verbatim Quotes
- “What Iran has demonstrated is that it has the power to close the strait and to keep it closed, even in the face of immense US and Israeli bombardment,” — *Gregory Brew*, Eurasia Group
- “The important thing is that flows through the Strait resume in significant volumes. That would start to eliminate the energy shock,” — *Alan Gelder*, Wood Mackenzie
- “We’re at dangerously low levels already,” — *Unnamed industry executive* (cited by Politico)
- “That shift suggests AIS-off behaviour is becoming an accepted operating protocol, not an exceptional measure,” — *Vortexa analyst*
What’s Next
Analysts expect the first substantial increase in transits only after mines are cleared and a durable cease-fire is secured. Kuwait Petroleum Corp. projects it will need 6–8 weeks to restore 70 % of its crude output, while Saudi Arabia continues to route oil through its East-West pipeline to Yanbu. The International Energy Agency warns that if Hormuz remains closed through the summer, a “risk premium of $10–20 per barrel” could become entrenched, pressuring global inflation and prompting accelerated investment in alternative pipelines and storage facilities across the Gulf.
