Strait of Hormuz shipping controls deepen as Iran requires IRGC vetting for transiting vessels

Iran appears to be tightening Strait of Hormuz shipping controls by requiring vessels to enter Iranian waters for vetting by the Islamic Revolutionary Guards Corps, with reports that some ships have paid to pass. Shipping data suggest traffic has dropped about 90% since the war began, raising oil prices and straining Asian importers, while Iran’s Kharg Island loadings reportedly remain steady.

Iran appeared to be tightening control over the Strait of Hormuz, a key route for oil exports. Shipping data and Iranian messages to a UN body suggested a system similar to a toll gate. Many vessels entered Iranian waters and faced checks by the Islamic Revolutionary Guards Corps. This shift risked formalising Iran’s ability to restrict passage and protect oil sales to China.

Shipping through the Strait dropped sharply after the Iran war began, affecting fuel supply and prices. Traffic fell by 90% since the war started, pushing global oil prices higher. Asian countries depending on Persian Gulf crude faced shortages. Only about 150 vessels, including tankers and container ships, transited since March 1, Lloyd’s List Intelligence reported.

Strait of Hormuz toll booth and IRGC vetting

Lloyd’s List Intelligence said Iran’s IRGC had imposed a "de facto toll booth regime\" in the Strait of Hormuz. Ships usually used a central two-lane channel, but many now sailed north around Larak Island. That path placed vessels inside Iranian territorial waters. Lloyd’s said entities seeking safe passage submitted cargo details, owners, destination, and full crew lists.

Approved vessels received a code and an escort by an IRGC vessel, Lloyd’s said. Oil shipments were prioritised and vessels faced geopolitical vetting. Not all ships paid a direct charge, yet at least two did. Lloyd’s List said tolls were paid in yuan. Some ships also appeared to get passage after diplomatic pressure, including two Indian LPG vessels.

Strait of Hormuz traffic patterns and ship safety risks

Recent voyages showed changing patterns among ships that crossed the Strait of Hormuz. Many vessels headed east, out of the Gulf. Iran-linked ships made up 24% of transits, Greece 18%, and China 10% by ownership or flag. A closer review found Iran-connected vessels made up 60% early in the war. In recent days, that share neared 90%.

Security fears also shaped behaviour at sea. About half of vessels switched off radio identification systems before transiting. They then reappeared on the other side in the Gulf of Oman. The U.N.’s International Maritime Organization said at least 18 ships were hit. At least seven crew members were killed. The IMO did not name any attacking nation.

Strait of Hormuz oil exports and China-linked buyers

Despite the disruption, Iran’s own export flows appeared to remain steady from Kharg Island. The terminal loaded 1.6 million barrels in March, Kpler data showed. That figure stayed close to prewar monthly loading totals. Most customers were small private refineries in China. The report said these buyers did not care about U.S. sanctions.

Strait of Hormuz legal questions and diplomatic response

Iran told the IMO it had taken steps it said were for safer seas. On Tuesday, the IMO received a letter from the Iranian government. The letter said Iran implemented \"precautionary measures\" to preserve maritime safety and security. It also claimed Iran acted within international law principles. The IMO condemned vessel attacks and urged coordinated security that respects navigation freedom.

Iran’s parliament also appeared to be moving towards a formal fee system, local media reported. Fars and Tasnim quoted lawmaker Mohammadreza Rezaei Kouchi on a plan to codify Iran’s sovereignty and oversight. The plan also aimed to raise revenue by collecting fees. This suggested a longer-term structure, beyond wartime controls.

Strait of Hormuz reactions from Gulf states and experts

Regional officials and analysts raised concerns about legality and economic impact. Article 19 of the UN Law of the Sea Treaty requires innocent passage for peaceful vessels. \"There’s no provision in international law anywhere to set up a toll booth and shake down shipping. & This is Iran using the element that they have right now, which is control of the Strait of Hormuz,\" said Sal Mercogliano.

Gulf leaders also criticised Iran’s approach as the conflict neared one month. Abu Dhabi National Oil Co. head Sultan al-Jaber used sharper language in Washington. \"Weaponizing the Strait of Hormuz is not an act of aggression against one nation,\" al-Jaber said. \"It is economic terrorism against every consumer, every family that depends on affordable energy and food.\"

Al-Jaber said higher costs would hit basic needs and wider economies. \"When Iran holds Hormuz hostage, every nation pays the ransom, at the gas pump, at the grocery store and at the pharmacy,\" al-Jaber said. \"No country can be allowed to destabilize the global economy in this way.\" The remarks reflected rising UAE frustration over shipping risks and energy price shocks.

The Gulf Cooperation Council also objected to any fees for passage. Secretary general Jasem Mohamed al-Budaiwi said collecting such payments was aggression. Al-Budaiwi said it violated the UN agreement on the law of the sea. The report also said payments could breach American and European sanctions on the Guard, a major power centre in Iran.

Evidence from ship movements, industry tracking, and Iranian communications pointed to tighter oversight in the Strait of Hormuz. Reduced traffic, attacks at sea, and new routing near Larak Island showed how shipping practices changed. At the same time, Iran’s own exports stayed steady and some vessels paid in yuan. International bodies and Gulf officials continued to challenge the approach.

With inputs from PTI