Iran retains control of Strait of Hormuz after ceasefire, new MoU fails to resolve dispute

Forty days of war and over sixty days of tense negotiations led to a memorandum of understanding (MoU) between the United States and Iran on June 17, 2026. However, the fundamental question of who controls the Strait of Hormuz remains unresolved. The strait, a critical energy chokepoint connecting the Persian Gulf to the Arabian Sea, was open to international shipping before the war began on February 28, 2026. Days after the US-led attack, Iran asserted control over the waterway and has since resisted all efforts to restore free navigation.

The US has employed a range of measures—bombing Iranian naval assets, issuing ultimatums, imposing a blockade on Iranian ports, and launching a short-lived operation to protect commercial shipping—but none have persuaded Iran to yield. After the MoU was signed, US President Donald Trump declared that the strait would be fully reopened for toll-free shipping. In response, Iran opened a new route along its coastline, claiming it would be safe, but this did not resolve the crisis.

Last week, an oil tanker off Oman’s coast was attacked by Iranian drones, leading to US retaliatory strikes and Iranian counterstrikes on US bases in the region. While both sides have agreed to halt further attacks, Iran has ruled out direct technical talks with the US, which were scheduled to continue this week, casting doubts on the implementation of the MoU.

At the heart of the problem lies a simple question: who controls the Strait of Hormuz?

What the MoU says

Under Article 5 of the MoU, Iran has promised to “make arrangements” for the “safe passage of commercial vessels, with no charges for 60 days only from the Persian Gulf to the Sea of Oman and vice versa.” It states that commercial traffic would immediately start and that Iran would remove mines and other impediments within 30 days. Crucially, the next line says Iran will conduct talks with Oman “to define the future administration and maritime services in the Strait of Hormuz, in discussions with other Persian Gulf littoral states, in line with applicable international law and the sovereign rights of coastal states.”

The agreement does not guarantee free passage beyond 60 days. It specifies that Iran—not the US—will negotiate the strait’s future with its neighbours. This means Iran has not relinquished its claims or control; rather, it has reasserted them.

The US, which has already lifted its maritime blockade, is unhappy with leaving such a vital waterway in Iranian hands. US Secretary of State Marco Rubio recently pressed Persian Gulf countries to oppose the Iranian plan. Oman opened an alternative route along its coast, but shortly after Rubio left, Iran attacked a Singapore-flagged tanker off Oman’s coast. The Islamic Revolutionary Guard Corps (IRGC) had earlier warned that traffic through “non-designated routes” could be dangerous. Tehran appeared willing to risk escalation rather than surrender control of Hormuz.

Why Hormuz matters

From Iran’s perspective, two decisions proved critical to its survival during the war: maintaining control of the strait and regionalising the conflict. The strait is not only economically vital—carrying about 20% of the world’s oil—but also strategically essential. Iran’s ability to control this chokepoint gives it leverage that it is unlikely to give up without a broader political settlement.

The MoU, while appearing to de-escalate, has merely postponed the fundamental dispute. Without direct talks and a clear agreement on the strait’s governance, the risk of further conflict remains high.