Iran's IRGC Navy Enforces Blockade in the Strait of Hormuz

On March 27, 2023, Iran's Islamic Revolutionary Guard Corps (IRGC) Navy turned back three vessels attempting to exit the Strait of Hormuz, marking a significant escalation in the ongoing maritime tensions in the region. The vessels included two Hong Kong-flagged mega-container ships, the CSCL Indian Ocean and CSCL Arctic Ocean, both chartered by China’s COSCO Shipping, and a Marshall Islands-flagged bulk carrier, the Lotus Rising. The IRGC stated that the strait was closed, directly contradicting claims made by U.S. President Donald Trump that Iran had agreed to allow some ships to pass through (Newsweek, 27 Mar).

NewsweekThree Ships Turned Back at Hormuz — The Blockade Outlasted the Commander Who Built It — GIZINT Signal

The blockade was declared by the IRGC on March 2, 2023, and represents the first time Iran has actively closed the Strait to transit traffic, despite previous threats during the Tanker War (1984–88) when Iran relied on these sea lanes for oil exports. The IRGC's actions come shortly after the assassination of Rear Admiral Alireza Tangsiri, who was believed to have overseen the blockade strategy. The IRGC's operational framework allows for decentralized command, which may have contributed to a more aggressive enforcement of the blockade following Tangsiri's death (Article-Chunk 2).

Three Ships Turned Back at Hormuz — The Blockade Outlasted the Commander Who Built It — GIZINT Signal

Vessel traffic in the Strait of Hormuz has reportedly decreased by over 90% since the onset of conflict in the Middle East, with the IRGC having attacked around 20 civilian ships as a show of force. The three vessels that were turned back had identified themselves as Chinese-owned and were attempting to navigate through a designated corridor for authorized vessels without prior permission. The IRGC's statement emphasized that "the Strait of Hormuz is closed," indicating a blanket denial of access to all vessels not pre-approved by Iranian authorities (Article-Chunk 3).

Newsweek

Iran's Foreign Ministry had previously announced safe passage for five nations, including China, yet the IRGC's actions suggest a more stringent enforcement of the blockade. The IRGC framed its actions as a response to what it termed "the lies of the corrupt US president," asserting that any movement through the strait would be met with a harsh response (Article-Chunk 1).

Newsweek

Critics argue that the blockade not only threatens international shipping but also undermines Iran's own economic interests, as the country relies heavily on oil exports through the Strait of Hormuz. The Iranian parliament is reportedly advancing legislation to impose a permanent toll of up to $2 million per transit, which could further complicate maritime operations in the region (Article-Chunk 2).

Newsweek

While the IRGC has claimed the strait is closed, reports indicate that some vessels, including those from China, have successfully navigated the waters after negotiating directly with Iranian authorities. This raises questions about the consistency of the blockade enforcement and the potential for selective access based on diplomatic negotiations (Article-Chunk 4).

Newsweek

• “Any movement through the strait will be met with a harsh response.” — IRGC Statement

Three Ships Turned Back at Hormuz — The Blockade Outlasted the Commander Who Built It — GIZINT Signal

• “The passage of any vessel to and from ports belonging to allies and supporters of the U.S. and Israel, to any destination and via any corridor, is prohibited.” — IRGC Statement

Newsweek

The situation in the Strait of Hormuz remains fluid, with ongoing tensions likely to impact global shipping routes and regional stability.

Newsweek