The Islamic Revolutionary Guard Corps Navy has shut the Strait of Hormuz, halting the daily passage of roughly 20 million barrels of oil through the 33-kilometer-wide waterway that connects the Persian Gulf with the Gulf of Oman. State media reported the closure on April 28 and stated it would remain in effect until further notice.
The strait, at its narrowest point just 33 kilometers across, carries about 20 percent of global oil consumption each day, making this the first actual closure after years of Iranian threats.
Strategic Waterway Shut Down
The IRGC Navy, which operates independently from Iran’s regular navy and relies on fast attack craft and anti-ship missiles, acted after the U.S. Navy’s Fifth Fleet conducted exercises in the region earlier in April. The Fifth Fleet is based in Bahrain.
Iran had previously threatened to close the strait in response to sanctions in 2018 and 2019, but those threats never materialized. This time, however, the IRGC Navy carried through, shutting one of the world’s most strategically important chokepoints. The Strait of Hormuz is the only sea passage from the Persian Gulf to the open ocean.
It sits between the coast of Iran and the Musandam Peninsula, with a stretch of that peninsula under the United Arab Emirates. Several Gulf countries rely on it as their sole maritime route for trade and energy exports.
Tankers carrying crude from Saudi Arabia, Iraq, Kuwait and the United Arab Emirates must pass through this chokepoint to reach global markets. The waterway’s narrow width and confined shipping lanes leave little room for tankers to maneuver if challenged by IRGC patrol boats or anti-ship missile batteries positioned along the Iranian coast. The 1975 Algiers Agreement gives Iran and Oman joint control over the shipping lanes.
Economic Shockwaves Across Asia
Oil prices surged over 10 percent in early trading following the announcement. For economies heavily dependent on oil imports that transit the strait, the disruption is immediate.
Japan, India and South Korea all rely on crude moving through this passage and now face potential supply chain interruptions. The closure affects not only petroleum but also gas routes that many economies depend on daily. Disruption at the strait can cause severe supply shortages across Europe and Asia. Previous tensions had seen Iran threaten to close the strait, and preparations to mine it were undertaken in some periods, yet no extended closure occurred during past Middle East conflicts.
This closure marks the first time the IRGC Navy has actually halted traffic, and the economic stakes are higher than ever. The daily flow of roughly 20 million barrels of oil represents about one-fifth of global consumption.
For tanker operators, insurers, and energy traders, the sudden halt introduces uncertainty and risk that will be priced into contracts worldwide.
What Comes Next
The U.S. Central Command has not yet issued an official response. The Fifth Fleet remains stationed in Bahrain, but CENTCOM has not announced any countermeasures.
The coming days will determine whether this remains a temporary closure or escalates into a broader confrontation. Oil-dependent economies across Asia are already calculating the cost. Japan, India and South Korea will likely press for diplomatic resolution, while watching for any U.S. military response.
For now, the strait is shut. The oil isn’t moving.
The IRGC’s fast attack craft and anti-ship missiles pose a tangible threat to commercial shipping in the confined waterway. Whether this action is a short-term pressure tactic or the beginning of a sustained blockade, the immediate consequence is clear: a critical artery of global energy supply has been severed, and the repercussions are spreading across the world.
