In less than a day, Iran declared the Strait of Hormuz open, watched tankers turn back under gunfire, then shut it again — leaving global energy markets in freefall and a ceasefire teetering on the edge of collapse.
For approximately eighteen hours on Friday 18 April, the world held its breath. Iranian Foreign Minister Abbas Araghchi announced, via a post on X, that the Strait of Hormuz — the narrow, 39-kilometre-wide chokepoint connecting the Persian Gulf to global energy markets — was "completely open" to commercial vessels for the duration of the Lebanon ceasefire. Oil futures plunged more than 10 percent in a matter of hours. US President Donald Trump celebrated on social media. Markets exhaled.
By Saturday evening, it was over. The Islamic Revolutionary Guard Corps (IRGC) had reimposed full closure of the strait, Indian-flagged merchant vessels had been fired upon, at least three additional tankers had been targeted according to the UK Maritime Trade Operations (UKMTO), and maritime traffic in the world's most critical energy corridor had ground back to a standstill. The 24-hour whiplash encapsulates, with brutal clarity, the fundamental deadlock driving the worst energy supply disruption in recorded history.
The False Dawn Of Friday
Araghchi's announcement came in direct response to the start of a 10-day US-brokered ceasefire between Israel and Hezbollah, which came into effect in the early hours of Friday morning. Tehran had long conditioned any reopening of the strait on an end to Israeli operations in Lebanon, and the foreign minister appeared to make good on that linkage. Oil markets took the announcement at face value, with West Texas Intermediate settling down 12 percent at $83.85 per barrel, and Brent crude futures finishing the day down 9 percent to approximately $90.
The reality on the water was far more ambiguous. Vessels attempting to exit the strait through the IRGC-designated route around Larak Island — Iran's newly imposed checkpoint — found themselves without clearance and turned back. Matt Smith, director of commodity research at the maritime data firm Kpler, was blunt: "They've clearly not been given approval to pass through." His colleague Matthew Wright, Kpler's senior freight analyst, called the announcement "a false dawn."
The world's largest shipping association, BIMCO, advised all vessels to avoid the strait entirely due to the continued threat of sea mines. The area was "not declared safe for transit at this point," said BIMCO's chief security officer, Jakob Larsen.
Iran's own parliament speaker, Mohammad Bagher Ghalibaf — who also serves as Tehran's chief negotiator in talks with Washington — publicly contradicted Araghchi almost immediately: "With the continuation of the [US] blockade, the Strait of Hormuz will not remain open." Semi-official Iranian outlet Tasnim News went further, criticising Araghchi for creating "various ambiguities about the conditions for passage, its details, and its mechanisms."
"The strait is still in a danger zone. The next 72 to 96 hours of actual tanker transits will determine whether confidence returns, or remains constrained." — Maria Bertzeletou, Senior Market Analyst, Signal
Trump, for his part, declared the Hormuz situation effectively "over" — while simultaneously confirming that the US naval blockade of Iranian ports would remain "in full force" until a comprehensive deal was concluded. The contradiction between Washington's celebration and its continued coercive posture handed Tehran the pretext it needed to reverse course within the day.
The Closure Returns — And Ships Come Under Fire
Saturday's events stripped away any remaining ambiguity. The IRGC issued a stark statement: "Control of the Strait of Hormuz has returned to its previous state... under strict management and control of the armed forces." The statement warned that "no vessel should make any movement from its anchorage in the Persian Gulf and the Sea of Oman, and approaching the Strait of Hormuz will be considered as cooperation with the enemy" and would be targeted.
The threat was not rhetorical. Iranian gunboats — fast attack craft of the type long deployed by the IRGC's naval forces — fired on at least two Indian-flagged merchant vessels in or near the strait. The IRGC had previously designated India a "friendly" nation and granted Indian ships passage rights. The attack on the Indian tanker Sanmar Herald, which had reportedly received IRGC clearance to transit before that clearance was abruptly revoked, encapsulates the arbitrary and dangerous nature of Iran's enforcement posture.
India's Ministry of External Affairs summoned the Iranian ambassador and conveyed what it termed "deep concern at the shooting incident." The Indian government's reaction carried symbolic weight: New Delhi has worked assiduously to maintain working relations with Tehran throughout the crisis, and the attack on vessels sailing under its flag signals a dangerous breakdown even in Iran's management of its "permitted" shipping.
The UKMTO, operated by Britain's Royal Navy, recorded multiple incidents. In the first, IRGC gunships fired on a tanker without radio warning; in the second, a container ship was struck by an unknown projectile causing damage to its cargo. Lloyd's List, the maritime intelligence firm, reported that traffic in the strait had "come to a halt" by Saturday evening, with radio transmissions from Iranian forces warning all ships that the waterway had returned to "strict management and control."
A statement attributed to Supreme Leader Mojtaba Khamenei — who has not made a public appearance since being chosen to succeed his assassinated father in late February — warned that Iran's navy was ready to inflict "new bitter defeats" on the United States and Israel. General Mohammed Naqdi, a senior Iranian military officer, added a pointed warning: "If the war starts again, we will use missiles whose production date is May 2026."
The Us Blockade And The Standoff Architecture
The US naval blockade of Iranian ports, which came into effect on 13 April following the collapse of the Islamabad Talks, lies at the centre of the current impasse. US Central Command stated on Sunday that 23 vessels had been forced to turn around since the blockade began. Washington insists the measure targets only ships travelling to or from Iranian ports and does not constitute a blockade of the strait itself — a distinction Tehran flatly rejects.
Iran's Supreme National Security Council has declared the blockade a "violation of the ceasefire" and stated that the Strait of Hormuz will not reopen until it is lifted. Iran's armed forces have threatened to extend operations to the Persian Gulf, the Sea of Oman, and the Red Sea — the latter via its Houthi proxy in Yemen, which formally entered the conflict in late March.
The result is an unprecedented dual-blockade architecture. The US blockades Iranian ports; Iran blockades the strait. Two sovereign naval forces — one the world's most powerful, the other asymmetrically capable and deeply entrenched in the geography — are contesting the same narrow waterway. As Professor Simon Mabon of Lancaster University observed in an Al Jazeera analysis: "Things are going to get more and more heated when you have essentially two different blockading forces competing for control over the Strait of Hormuz. I think that really ratchets up the tensions."
The IRGC's so-called "mosquito fleet" — hundreds of small, fast attack craft concealed in cave-fortified bases along the Iranian coastline — remains operationally intact despite significant losses to Iran's regular navy, which US Chairman of the Joint Chiefs Gen. Dan Caine said on 8 April had been largely destroyed, with more than 90 percent of its main warships sunk. US warships enforcing the blockade are remaining well outside the strait, in the Gulf of Oman or further into the Arabian Sea, where they are far less vulnerable to IRGC drone and missile attacks.
Diplomacy: Talks Stalled, Ceasefire Expiring
The diplomatic picture is no less fraught. The two-week US-Iran ceasefire, agreed on 7 April, expires on Wednesday 22 April. A second round of face-to-face negotiations — following the inconclusive Islamabad Talks led by Vice President JD Vance on the American side and Ghalibaf on the Iranian side — has not been formally confirmed, though Pakistani security sources cited by Al Jazeera on Sunday say preparations are already underway in Islamabad: the Serena and Marriott hotels are being cleared of guests, and two US C-17 Globemaster aircraft have landed at Noor Khan Airbase in Rawalpindi.
Ghalibaf, in a televised address late Saturday, offered a revealing articulation of Iran's strategic calculus. He portrayed the ceasefire itself as a form of victory — arguing that the US and Israel had failed to topple the government or rally international backing around the strait. "When the enemy fails to achieve its objectives, it means it has been defeated," he said. He insisted that any eventual deal must proceed on a "step-by-step" basis with reciprocal actions, and that the US must "earn the trust of the Iranian people."
The sticking points are substantial. Beyond the Strait of Hormuz, the two sides remain deeply divided on the fate of Iran's stockpile of highly enriched uranium and its ongoing enrichment programme. Iranian President Masoud Pezeshkian publicly challenged Trump's authority on the nuclear file on Sunday, asking: "Who is he to deprive a nation of its rights?" Iranian Deputy Foreign Minister Saeed Khatibzadeh said no date had been set for a new round of talks and accused Washington of holding "maximalist" positions.
Meanwhile, Iran's intelligence apparatus continues to operate at war footing domestically. The IRGC's Kerman province unit announced the arrest of 51 individuals on charges of "intelligence gathering, armed organisation and inciting unrest" allegedly linked to US, Israeli and British networks. Authorities in Jalfa separately detained four people — including two foreign nationals found with Starlink satellite internet terminals — on espionage charges. Internet access inside Iran has been restricted for over 1,200 hours, according to the digital rights monitor Netblocks, now entering its eighth consecutive week.
"It does feel as if we are drifting away from a deal — but not irretrievably. Both sides were beginning to believe the deal was possible." — CNN Analysis, 19 April 2026
The Energy Reckoning
The human and economic cost of the strait's closure continues to compound. Ship-tracking data compiled by Kpler shows that only 45 ships have entered or exited the strait since the ceasefire took effect on 8 April — compared to the hundreds that transited daily before 28 February. Tanker transit levels remain approximately 90 percent below pre-war figures. The International Energy Agency has assessed that more than 80 energy facilities across the region have been damaged, many severely, and that restoring output to pre-war levels could take up to two years.
Analysts are warning that the supply crunch in Asia is already critical. Refineries across the continent, heavily dependent on Gulf oil, are drawing down onshore inventories at unsustainable rates. Even if the strait were to reopen fully tomorrow, it would take weeks for substantial volumes of Persian Gulf crude to reach buyers in Asia and Europe, and months before pump prices recovered to anything approaching pre-war levels. The IEA stated this week that "resuming flows through the Strait of Hormuz remains the single most important variable in easing the pressure on energy supplies, prices and the global economy."
Iran's own deputy labour minister, Gholamhossein Mohammadi, acknowledged on Sunday that the war had already resulted in the loss of over one million jobs and the unemployment, directly or indirectly, of two million Iranian citizens.
European powers are attempting to insert themselves into the post-conflict framework even as the conflict continues. French President Emmanuel Macron and British Prime Minister Keir Starmer announced a conference at the Élysée Palace — the "Initiative for Maritime Navigation in the Strait of Hormuz" — aimed at coordinating maritime traffic once hostilities end and potentially establishing "a strictly defensive multinational mission when security conditions permit." The initiative underscores European anxiety about both the economic consequences of the closure and Washington's unilateral management of the crisis.
China and Russia have been active on the diplomatic margins. Both vetoed a UN Security Council resolution on 7 April that would have authorised military force to open the strait. Beijing has simultaneously pursued bilateral arrangements with Tehran to secure passage for Chinese-flagged vessels, while Chinese foreign minister Wang Yi has spoken with Araghchi as recently as Saturday, with the Iranian foreign minister thanking China for its Security Council veto.
Pakistan, for the second time, appears set to host the next round of US-Iran negotiations — a role that has significantly elevated Islamabad's regional profile and diplomatic standing. The district administration has ordered restrictions on heavy transport and public buses in the capital ahead of anticipated talks, with nearly 20,000 security personnel reported to be on standby.
Mutually Incompatible Red Lines
The events of the last 24 hours constitute more than a tactical reversal. They reveal the fundamental structural contradiction at the heart of the current impasse: Washington and Tehran have constructed mutually incompatible red lines — the US blockade of Iranian ports and Iran's closure of the strait — which each side demands the other abandon first. Neither has shown willingness to move unilaterally.
Tehran's behaviour also reflects a documented internal tension within the Iranian decision-making architecture. Araghchi's diplomatic opening — real or performative — was contradicted within hours by the IRGC and the parliament speaker. Whether this represents deliberate signalling strategy or genuine institutional incoherence over who controls Hormuz policy remains analytically contested. Professor Mabon's observation is apt: it is simultaneously possible that Friday's opening was a bargaining move and that it reflected genuine uncertainty in Tehran about who is setting the terms.
What is not contested is the timeline pressure. The ceasefire expires Wednesday. Trump has stated he does not know whether he will extend it, and has explicitly warned that the alternative is a resumption of airstrikes. Iran's military says it is ready. A senior Israeli official described the ceasefire as "very fragile." New York Times reporting, citing US intelligence assessments, indicates Iran retains access to approximately 70 percent of its pre-war ballistic missile stockpile — a significant retained deterrent capability.
The next 72 hours will determine whether the Islamabad channel produces a framework sufficient to extend the ceasefire and begin de-escalating the blockade architecture, or whether the world's most critical energy chokepoint becomes the flashpoint for a renewed and potentially wider phase of the conflict. For the global economy — already absorbing the largest oil supply disruption in history — the margin for miscalculation has never been thinner.
Illustration: Perplexity (based on a related picture in the Iran International)