Strait of Hormuz: Effectively Closed Amid Fragile Ceasefire and Escalating Tensions

Update as of 4/13/2026 12:20pm Central

Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC - Cropped from: http://visibleearth.nasa.gov/view_rec.php?id=2363

The Strait of Hormuz, the narrow chokepoint through which roughly one-fifth of global oil and a significant share of liquefied natural gas (LNG) normally flows, has been largely paralyzed since late February 2026. Iran began restricting or blocking transits in response to U.S.-Israeli military strikes that began on February 28, which targeted Iranian facilities and led to Khamenei's death.

From Whitehouse.gov the President has ordered a U.S. naval blockade of the Strait of Hormuz

Scale of disruption: Shipping traffic has dropped to well below 10% of normal levels. On some days, only a handful of vessels (e.g., 3–7 ships in 24 hours versus ~140 normally) have passed, mostly dry bulk carriers with minimal oil tankers. Hundreds of vessels, including nearly 400 oil tankers, remain stranded in the Persian Gulf or anchored nearby, with reports of 20,000+ seafarers affected.

Iran's actions: Iranian state media and the IRGC have declared the strait "closed" or heavily restricted at times, requiring permission from the Sepah (IRGC) navy, warning ships to stay in Iranian territorial waters, and threatening attacks on unauthorized vessels.

Mines were reportedly laid, and selective tolls (reportedly over $1 million per ship in some cases) were mentioned. Tehran has cited ongoing Israeli strikes (including in Lebanon) as justification for restrictions, framing it as leverage amid the conflict.

A significant contributor to the longer recovery timeline is infrastructure damage from Iranian retaliatory missile and drone strikes on energy facilities in neighboring Gulf countries.

These attacks hit key sites including:

• Qatar’s Ras Laffan Industrial City (the world’s largest LNG export hub), causing extensive damage, fires, and knocking out approximately 17% of Qatar’s LNG production capacity. QatarEnergy has indicated that repairs for affected portions could take 3–5 years in some assessments.

• Energy infrastructure in Saudi Arabia (including the Ras Tanura refinery, East-West Pipeline, and other sites) and the UAE (including Habshan gas facilities), leading to temporary halts, fires, and operational disruptions.

  
  

Ceasefire context: A U.S.-Iran ceasefire was announced around April 7–8, 2026, with reopening the strait as a core U.S. demand. President Trump conditioned pauses in strikes on "complete, immediate, and safe" opening without limitations or tolls. However, traffic has not meaningfully resumed. Iran has maintained control through threats and selective permissions, while the White House has called continued restrictions "completely unacceptable."

As of April 12, the situation remains tense:

• Traffic data shows minimal transits (e.g., 17 vessels on April 11 in some reports, still far from normal).

• The U.S. has begun mine-clearing operations with Navy warships and announced plans for a naval blockade to prevent ships from paying Iranian tolls or transiting under restricted conditions. Iran has pushed back, calling any U.S. moves a "self-made problem."

• Global impacts include soaring oil prices, elevated war-risk insurance (over 16x normal), and broader supply chain strain for energy, fertilizers, and goods. Restarting full flows could take weeks to months even if restrictions lift, due to damaged infrastructure across the region.

The strait has never been formally "owned" by any single nation under international law, and its closure or severe restriction affects not just regional players but global energy markets. UAE officials and others have stressed that it is a vital international waterway whose disruption harms economies worldwide, including ordinary Iranians facing the downstream effects of isolation and economic pressure.

Key updates as of 4/13/2026

• The U.S. naval blockade of all ships entering or leaving Iranian ports in the Strait of Hormuz officially began at 10:00 a.m. ET (2:00 p.m. GMT / 5:30 p.m. Iran time) today.

• Ship traffic through the strait has largely halted in response, according to maritime intelligence firms like Lloyd’s List. Very few vessels are moving.

• President Trump warned that any Iranian warships approaching the U.S. blockade will be “immediately eliminated.” He also claimed the majority of Iran’s navy has already been “obliterated.”

• Iran has denounced the blockade as “an act of piracy” and threatened retaliation against ports across the Persian Gulf and Gulf of Oman.

• The fragile U.S.-Iran ceasefire is still technically holding for now, but analysts say this dueling blockade situation (Iran’s restrictions + U.S. enforcement) puts it at serious risk of collapse.

• Oil prices have surged again, topping $100 per barrel in some trading.

• No major clashes have been reported in the first hours of the blockade, but the risk of escalation remains high.

This story is developing rapidly. Check back for further updates.