Iran Reaffirms Strait of Hormuz Closure as Ceasefire Deadline Approaches

On April 17, Iranian Foreign Minister Abbas Araghchi posted a message declaring the Strait of Hormuz "fully open and ready for full passage" [1]. Oil prices cratered — WTI fell 12% in a single session to $83.85 [2]. For a few hours, it looked like the worst energy crisis since the 1973 Arab oil embargo might be winding down.

Twenty-four hours later, IRGC gunboats fired on a tanker attempting to transit the strait. Iran reversed course, reinstating closure and declaring it would remain until the United States completely lifts its naval blockade of Iranian ports [3]. Senior IRGC figures reportedly called Araghchi an "idiot" [4]. By April 19, Brent crude had surged back toward $98 per barrel [5].

The episode — 48 hours of diplomatic whiplash that erased and then recreated billions of dollars in market value — captures the central question of this crisis: who actually controls Iranian decision-making, and can any agreement survive the answer?

How We Got Here

The Strait of Hormuz crisis is inseparable from the broader 2026 Iran war. In January, Iranian security forces killed thousands of civilians during the country's largest protests since the 1979 revolution. President Trump threatened military action and ordered the largest US buildup in the Middle East since 2003 [6].

On February 28, the United States and Israel launched coordinated airstrikes against Iran. At 06:45 UTC, Israeli jets began decapitation strikes across 13 provinces. Supreme Leader Ali Khamenei was killed at his residential compound, along with Defense Minister Aziz Nasirzadeh, IRGC commander Mohammad Pakpour, and approximately 40 other officials [7]. HRANA, an Iranian human rights organization, documented 56 strikes that killed at least 85 civilians and 11 military personnel [7].

Iran retaliated with missile and drone strikes against Israel, US bases, and Arab Gulf states. On March 2, the IRGC declared the Strait of Hormuz closed to Western-allied shipping [8]. On March 9, the Assembly of Experts named Mojtaba Khamenei — Ali Khamenei's son, born in 1969 — as the new Supreme Leader. Reuters reported that Mojtaba was severely injured in the same strike that killed his father, suffering facial disfigurement and the loss of a leg. He has not appeared publicly since his appointment [9].

The Ceasefire and Its Fractures

On April 8, the US and Iran agreed to a two-week ceasefire mediated primarily by Pakistan, with Chinese participation in the negotiations [10]. The ceasefire expires around April 22-23.

The terms reveal the gulf between the two sides. Iran's 10-point proposal demanded non-aggression guarantees, continuation of Iran's control over the Strait, acceptance of its uranium enrichment program, and the lifting of all primary and secondary sanctions [11]. The US counterproposal — reported to contain 15 points, though it remains unpublished — reportedly demands Iran hand over its highly enriched uranium, accept limits on defense capabilities, disband proxy groups, and reopen the Strait [12].

A separate dispute over Lebanon has further complicated the process. Netanyahu rejected Lebanon's inclusion in the ceasefire framework; Iran and Pakistan contend that Lebanon was part of the deal, and Iran has threatened to terminate the ceasefire entirely if Israel continues military operations there [12].

Trump stated on April 19 that a US delegation is heading to Pakistan for continued negotiations [5].

Twenty Million Barrels a Day

The Strait of Hormuz is a 21-mile-wide channel between Iran and Oman through which roughly 20% of the world's oil supply passes daily. In the first half of 2025, approximately 20.9 million barrels per day of crude oil and petroleum products transited the strait [13]. In dollar terms at recent prices, that represents over $2 billion worth of oil flowing through the channel every 24 hours.

The IEA has characterized the March closure as the "largest supply disruption in the history of the global oil market" [14].

Source: EIA / IEA

Data as of Apr 19, 2026CSV

Ship transits collapsed from roughly 130 per day in February to just 6 in March — a 95% drop [14]. Even during the brief April 17 "reopening," traffic remained well below pre-crisis levels.

Source: Lloyd's List / CENTCOM

Data as of Apr 19, 2026CSV

The disruption extends beyond oil. Approximately one-quarter of global LNG trade transits the strait, primarily from Qatar, the world's largest LNG exporter [13]. South Korea, Japan, and China — which collectively import more than 65% of their crude oil through Hormuz — face the most immediate supply risk [15]. India, which sources roughly 60% of its oil imports from Gulf producers, is similarly exposed [15].

European countries have more diversified supply chains but still depend on Gulf oil for a significant share of imports. Gulf states themselves face a paradox: Saudi Arabia and the UAE possess alternative pipeline routes — notably the East-West Pipeline and the Abu Dhabi Crude Oil Pipeline — but these can only handle a fraction of normal export volumes [13].

Iran's Military Hand

Iran's ability to close and hold the strait rests on three pillars: mines, missiles, and fast-attack boats.

Iran possesses an estimated 2,000 to 6,000 naval mines, including contact mines, moored mines, and sophisticated bottom-influence mines triggered by acoustic, magnetic, or pressure signatures [16]. These are stored in a network of tunnels and caves along Iran's southern coast and can be deployed from small vessels, dhows, and submersibles — making pre-deployment detection difficult [16].

Iranian anti-ship missile systems include the Noor (a Chinese C-802 derivative), a sea-skimming cruise missile capable of covering the entire strait from concealed coastal positions, and the Khalij Fars, an anti-ship ballistic missile with a 300-kilometer range and electro-optical terminal guidance [17]. Mobile missile batteries are deployed along nearly 1,000 miles of Iranian coastline [17].

The IRGC Navy operates over 100 fast-attack boats capable of speeds between 50 and 70 knots, equipped with machine guns, rockets, anti-ship missiles, torpedoes, and mine-laying capability [17]. These are designed for swarm tactics — overwhelming adversary defenses through simultaneous attacks from multiple vectors.

US intelligence assessed in early April that despite the February strikes, Iran "maintains significant missile launching capability" [18]. As of March 8, Iran had confirmed attacks on at least 21 merchant vessels [8].

The US Response

The US military response has operated on two tracks: a naval blockade of Iran and freedom-of-navigation operations to reopen the strait.

US Central Command established a blockade on all ships entering or leaving Iranian ports and coastal areas, while explicitly stating this "will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports" [19].

On April 11, USS Frank E. Petersen (DDG-121) and USS Michael Murphy (DDG-112) became the first US warships to transit the strait since the war began, establishing a corridor for merchant vessels [20]. Mine countermeasures ships — USS Canberra (LCS-30), USS Santa Barbara (LCS-32), and USS Tulsa (LCS-16) — deployed with purpose-built mine-clearing packages [20].

The UN maritime chief stated that "no country can legally restrict navigation in Strait of Hormuz" under international law, specifically the UN Convention on the Law of the Sea provisions governing international straits [21]. Iran, however, has not ratified UNCLOS.

The realistic timeline for mine clearance is measured in weeks to months. The 1988 Operation Earnest Will and the post-1991 Gulf War mine-clearing effort took months with far fewer mines in the water [16]. The current scope of Iranian mine-laying remains uncertain but is presumed to be extensive.

Oil Prices: The Fever Chart

WTI crude oil has traced a path that mirrors the conflict's escalation. From around $60 per barrel in late 2025, prices rose sharply after the February strikes, surged past $114 in early March when the strait first closed, and have since oscillated violently with every diplomatic development [22].

Source: FRED / EIA

Data as of Apr 13, 2026CSV

The Dallas Federal Reserve estimated that a sustained closure would push average WTI to $98 per barrel [23]. Current prices — Brent at roughly $97-98 and WTI above $93 as of April 19 — already reflect that scenario [5].

War-risk insurance premiums for vessels transiting the strait have risen from 0.125% to between 0.2% and 0.4% of a ship's insured value per transit [24]. For very large crude carriers, that represents an increase of approximately $250,000 per voyage [24].

UNCTAD warned that the disruption threatens to slow global merchandise trade growth from approximately 4.7% in 2025 to between 1.5% and 2.5% in 2026, with increased food costs and cost-of-living pressures falling disproportionately on vulnerable populations in the developing world [25]. The Dallas Fed projected that global GDP growth could fall by 0.2 to 0.3 percentage points depending on whether the disruption lasts one or two quarters [23].

Emerging markets dependent on oil imports face the sharpest fiscal pressure. Countries without substantial strategic petroleum reserves — much of South and Southeast Asia, sub-Saharan Africa, and parts of Latin America — have limited buffers. The combination of higher energy costs, elevated shipping rates, and rising insurance premiums compounds into inflationary pressure that monetary policy struggles to offset without slowing growth further.

The IRGC Versus Everyone Else

The April 17-18 reversal exposed a factional rupture at the top of the Iranian power structure that may be the single most important variable in how this crisis resolves.

Foreign Minister Araghchi — associated with Iran's pragmatist wing — announced the strait's reopening in what appeared to be a diplomatic gesture ahead of ceasefire renewal talks. Within hours, the IRGC overruled him, fired on ships, and reimposed the closure [3]. Iranian state media slammed Araghchi's announcement, saying it allowed Trump to claim a premature victory [4].

Euronews assessed that "the IRGC appears to now shape Iran's decisions" rather than civilian political leadership [26]. Fortune reported that the episode exposed "a fight between different factions" within the regime [27]. The Jerusalem Post documented how IRGC commanders publicly challenged Araghchi's authority [28].

The structural explanation centers on Mojtaba Khamenei. The new Supreme Leader remains largely inaccessible due to security conditions and reported injuries. Only senior IRGC commanders maintain direct communication with him; civilian leadership, including the president and foreign ministry, reportedly lacks direct access [9]. This arrangement gives the IRGC de facto decision-making power, regardless of what civilian officials negotiate or announce.

The dynamic creates a specific problem for diplomacy: even if Araghchi or other civilian officials reach an agreement with the US, there is no guarantee the IRGC will honor it. The ceasefire's remaining days will test whether any faction can consolidate enough authority to make and keep commitments.

Some hardliners view the Hormuz closure not as a temporary tactic but as a long-term revenue opportunity. Iranian MP Amir-Hossein Sabeti declared that Iran could gain "a third source of income called the Strait of Hormuz," and strategic analyst Mehdi Mohammadi — an adviser to the parliament speaker — claimed Iran could earn $800 billion annually from the waterway through transit fees [29].

The Skeptics' Case

Not everyone views the Hormuz closure as sustainable leverage. Foreign Affairs and the Foundation for Defense of Democracies both argued in an April analysis that "for Iran, Hormuz is more a weakness than a weapon" [30].

The logic: over 90% of Iran's seaborne trade passes through the strait [30]. Oil and gas constitute approximately 25% of Iran's GDP and 80% of its export earnings [30]. Iran cannot reroute its exports around the closure — unlike Saudi Arabia and the UAE, it has no alternative pipeline infrastructure to bypass the waterway. A sustained closure harms Iran as much or more than its adversaries.

This argument has historical grounding. Iran threatened to close the strait in 2008, 2011-12, and 2018-19 without following through [31]. During the 2011-12 crisis, most analysts concluded the threat was a negotiating tactic designed to deter additional sanctions rather than a genuine military plan.

However, the 2026 situation is unprecedented: Iran has actually executed the threat for the first time. The confirmed attacks on merchant vessels and documented mine-laying represent a qualitative break from past rhetoric [8]. The "bluff" framework, whatever its historical validity, no longer fully applies.

The skeptics' stronger argument may be about sustainability rather than intent. Under a US naval blockade, Iran's own imports and exports are already disrupted. The Hormuz closure adds pressure on Iran's adversaries but does not relieve pressure on Iran itself. The question is whether the IRGC views this as an acceptable cost of maintaining leverage — or whether economic reality will force a reassessment.

What Happens Next

Three days remain before the ceasefire expires. Several factors will determine whether the crisis escalates or stabilizes:

Mine clearance progress. US mine countermeasures vessels are deployed, but the scale of Iranian mine-laying is unknown. If the US can demonstrate that it can keep a corridor clear, Iran's leverage diminishes. If mines continue to disable or deter merchant shipping, the closure holds regardless of diplomatic declarations.

The IRGC-civilian power balance. Any agreement reached through Pakistani mediation must survive internal Iranian politics. The April 17-18 episode demonstrated that the IRGC can reverse civilian diplomatic commitments within hours. Whether Mojtaba Khamenei — or anyone else — can impose discipline on the IRGC remains unclear.

Oil market dynamics. Brent crude near $100 per barrel creates political pressure on Trump, who has made low energy prices a central domestic promise. But it also creates pressure on oil-importing allies whose support the US needs for sustained military operations. The longer prices remain elevated, the stronger the incentive for all parties to find a resolution — or for consuming nations to seek alternatives that reduce Hormuz's significance.

Strategic petroleum reserve releases. The US Strategic Petroleum Reserve and IEA coordinated stockpile releases can cushion short-term supply disruptions, but these are finite. A 30-day disruption is manageable; a 90-day disruption would strain reserves significantly, particularly in Asian countries with thinner buffers.

The 2026 Strait of Hormuz crisis has already produced the largest energy supply disruption in history, reshaped the global military balance in the Persian Gulf, and exposed fractures within the Iranian state that may outlast the current conflict. Whether the ceasefire holds or collapses, the crisis has demonstrated that the world's most important oil chokepoint is no longer a theoretical vulnerability — it is an active one.