Why Iran insists on controlling the Strait of Hormuz
The memorandum of understanding (MoU), signed by the U.S. and Iran on June 17, promising to extend the ceasefire and launch talks on Iran’s nuclear
The memorandum of understanding (MoU), signed by the U.S. and Iran on June 17, promising to extend the ceasefire and launch talks on Iran’s nuclear programme and Western sanctions, is falling apart. U.S. President Donald Trump has declared that the “ceasefire is over”. According to Tehran, parts of the MoU have been rendered “ineffective” by American actions. Both sides have accused each other of violating the MoU. The U.S. has carried out air strikes on hundreds of targets across Iran, while Tehran has retaliated by attacking U.S. bases in several Persian Gulf countries as well as Jordan. At the heart of the renewed violence lies a dispute over Article 5 of the MoU, which requires Iran to “make arrangements” for the “safe passage of commercial vessels” through the Strait of Hormuz. Iran has designated a new shipping route along its coast, while the U.S. Navy has cleared an alternative route along Oman’s coast. Iran sees this move as a violation of the clause by the U.S. Last week, three tankers using the U.S.-backed route came under Iranian attacks. The U.S. says the attacks constituted a violation of the MoU by Iran. It launched air strikes in Iran, and the Islamic Revolutionary Guard Corps (IRGC) has since announced the temporary closure of the strait. In the MoU, the U.S. has made several concessions to Iran.
It lifted its maritime blockade, issued a sanctions waiver for Iranian crude and other petroleum products and also promised that Iran would get access to some of its frozen funds. After last week’s escalation, the U.S. has revoked the waiver and reimposed some sanctions on Iran. But Tehran seems determined to retain its grip over the strait, one of the world’s most important commercial chokepoints, even at the risk of an all-out war and reversal of the purported gains of the MoU. Why? A battlefield at sea Both the U.S. and Iran see the Strait of Hormuz as critical to shaping the future balance of power in the Persian Gulf. While Gulf countries are exploring ways to reduce their dependence on the strait through alternative pipelines and trade corridors, such efforts are unlikely to significantly diminish its importance any time soon. In 2025, about 20 million barrels of oil a day passed through the strait, along with more than 112 billion cubic metres of LNG. It also handled one-third of global seaborne urea trade, one-third of global seaborne ammonia trade, and 40% of global seaborne sulphur exports — together accounting for roughly 30% of global fertiliser trade. The Strait of Hormuz will therefore remain a critical artery linking the Persian Gulf to the global economy. Control over the waterway would give any regional power enormous strategic and economic leverage.
The BriefWire