In March 2025, Iran hosted the “Maritime Security Belt-2025” joint naval exercise near the strategic port of Chabahar, in the Gulf of Oman. The drills featured:

• Live-fire day and night shooting drills. These in synchronized aerial target engagement and heavy machine gun exercises.
• Tactical formations and mock rescue missions. Special operations teams from Iran and China conducted covert approaches to “hijacked” merchant vessels, boarding and “rescuing” hostages in simulated scenarios.
• Aerial integration. For the first time, the drills expanded to include helicopters and fixed-wing aircraft operating in deeper waters, demonstrating improved coordination and operational reach.
• Maritime review and parade. The exercise concluded with a joint naval parade, underscoring the interoperability and growing sophistication of the participating navies.

Rear Admiral Mostafa Tajeddini, Iran’s deputy operations commander, emphasized the complexity and precision of the drills, noting the seamless integration between the Iranian Navy, IRGCN, and their Russian and Chinese counterparts.

Persistent Gray Zone Tactics in the Strait of Hormuz

While large-scale naval exercises often dominate headlines, Iran’s gray zone tactics in the Strait of Hormuz are a persistent, day-to-day threat to the regional order. In June 2023, U.S. and British naval forces responded to a distress call from a merchant vessel harassed by three Iranian fast-attack craft within the strait; the intervention of the USS McFaul and HMS Lancaster helped deter further escalation.

More recently, in June 2025, following U.S. strikes on Iranian nuclear sites, Iran’s parliament endorsed a proposal to close the Strait of Hormuz—though the ultimate authority to enact such a closure lies with the Supreme National Security Council. This move stands as a clear example of gray zone signaling, designed to raise the specter of escalation without resorting to immediate action.

Iran’s tactics are not limited to physical harassment. Recent Windward data reveals that, between June 15–18, an average of nearly 970 ships per day have experienced GPS jamming as they transited the Arabian Gulf and Strait of Hormuz, with some days seeing more than 1,100 vessels affected. This widespread electronic interference has caused ships’ AIS signals to appear in implausible locations—such as Iranian ports, the Omani desert, and near Dubai—severely disrupting navigation and safety for commercial vessels. 

The sudden onset of these disruptions, coinciding with the latest outbreak of conflict in the Middle East, has led to delays, diversions, and significant shifts in routing as shipowners, insurers, and energy traders reassess maritime security. The persistent jamming has also contributed to a notable decline in Strait transits and a sharp rise in freight and insurance premiums.

Strategic and Economic Stakes: The Strait of Hormuz

The Strait of Hormuz is a critical chokepoint for global oil trade, handling about a quarter of the world’s seaborne oil and a fifth of all oil movements. Any disruption would cause a massive spike in oil prices, affecting economies globally, especially those of China, India, Japan, and South Korea, which rely heavily on oil transiting the strait.

Iran does not have the ability to “close” the strait in a conventional sense, but it can make the waterway perilous through harassment, mining, missile attacks, or cyberattacks. Most analysts believe a full blockade is unlikely because it would be “economic suicide” for Iran, given the country’s own reliance on the strait for exports and the risk of a massive military response from the U.S. and its allies. Instead, increased harassment of commercial shipping—such as attacks on specific vessels or the deployment of sea mines—is seen as more likely than a total blockade.

While Tehran continues to signal the threat of closing the Strait of Hormuz and leverages cyber and proxy operations in pursuit of this, its ability to sustain such an operation is undermined by its own reliance on the strait and the risk of overwhelming international retaliation. The collapse of Iran’s once-formidable regional network further underscores the broader decline in the Islamic Republic’s capacity to project maritime influence. In light of these realities, Iran’s options in the Strait of Hormuz are narrowing, reflecting a broader trend of diminishing leverage.