Iran Says Strait of Hormuz Closed Again as U.S. Reports 55 Ships Transited, Lake Lucerne Summit Held In Switzerland

The U.S. and Iran stated opposite positions on whether the Strait was open even as their negotiators gathered in Switzerland.

PERSIAN GULF — Iran’s Islamic Revolutionary Guard Corps (IRGC) Navy said the Strait of Hormuz was closed again on June 20 and into June 21, broadcasting audio warnings on maritime radio that vessels should stay clear of the waterway or face security risks.

Hours earlier on June 20, U.S. Central Command (CENTCOM) reported that commercial traffic through the same Strait had increased, with 55 merchant ships transiting and moving more than 17 million barrels of oil to global markets, according to its own statement.

U.S. Vice President JD Vance said the Strait remains open, while President Donald J. Trump stated there would be no tolls in the waterway during the 60-day ceasefire period and none afterward unless imposed by the United States.

The two governments, the principal parties to the June 17 framework, stated opposite positions on whether the Strait was open even as their negotiators gathered in Switzerland.

Current Traffic Status

Commercial traffic through the Strait rose on June 20 after a stretch of near-zero volumes during the blockade and closure periods, according to CENTCOM.

The command said safe passage “remained intact today as 55 merchant ships transited,” moving large amounts of cargo and the 17 million barrels cited above. Ship-tracking data had shown transits collapse toward zero during the earlier closures.

Independent ship-tracking measured the resumption as real but smaller than the U.S. figure. The International Monetary Fund’s PortWatch choke-point monitor recorded transits near zero through June 14, against a pre-crisis norm of about 94 ships per day.

The commercial ship-tracking firm Kpler counted at least 20 tankers crossing on June 18, its highest since June 2, and about 25 vessels across all classes that day, of which 18 followed the route Iran designated.

That total stayed well below the pre-war norm of more than 100 ships a day, and no independent tracker matched CENTCOM’s June 20 figure of 55 ships.

According to the Institute for the Study of War, Iran has replaced the pre-war “traffic separation scheme” with one of its own across the Strait, routing transit through waters Tehran claims to control.

That mechanism lets Iran shape passage without firing on a ship, which is part of why the two sides can present the same water as both open and closed at once.

The cost of moving oil through the choke-point has climbed sharply. War-risk insurance for a single transit reached roughly 3 to 8 percent of a vessel’s hull value for seven days, about $3 million to $8 million for a large tanker against pre-crisis levels near 0.001 percent, according to the reinsurance broker Howden Re and S&P Global Commodity Insights.

Industry trackers reported roughly 100 container ships held inside the Gulf, awaiting clearer routing guidance.

Assessment: The 55-ship total represents a significant increase compared to the near-zero traffic during the late-February blockade, but a single day of activity does not eliminate the underlying closure risk.

Insurance underwriters continue to base pricing on the standing closure declaration rather than daily transit figures. As a result, the cost of coverage provides a more reliable indicator of control over the lane than ship counts alone.

Maritime Security Advisories and Threat Level