Can Iran close the Strait of Hormuz?

Iran holds the north shore of the strait and maintains IRGC naval bases along that coastline. It also controls three islands inside the strait: Abu Musa and the Greater and Lesser Tunbs, seized in 1971 and still disputed with the UAE. From those positions, Iran can deploy Noor anti-ship cruise missiles, sea mines, and swarms of fast-attack craft (the IRGC’s favoured asymmetric tactic). Tehran has threatened closure many times since the 1980s Tanker War. Each time, the threat was credible enough to move oil markets.

What actually happened: on 28 February 2026, US-Israeli airstrikes (Operation Epic Fury) triggered the IRGC to close the strait to commercial shipping. A formal closure declaration followed in early March 2026. This was the first sustained closure in the strait’s modern history as a major oil corridor. Roughly 550 vessels were stranded on either side within weeks, and the world’s major carriers either suspended Hormuz transits or rerouted south of the Cape of Good Hope.

The self-deterrent has always been that Iran exports its own oil through the strait, primarily to China. A prolonged closure costs Iran export revenue and political goodwill with its primary customer. That economic brake does limit the duration a closure can be maintained without severe self-harm. In the 2026 case, however, the IRGC overrode that constraint in response to direct strikes on Iranian territory, demonstrating that military confrontation removes the self-deterrent.

Under international law, the Strait of Hormuz is an international strait governed by UNCLOS Part III. Transit passage rights apply: all vessels, civilian and military, have the right to unimpeded transit. A unilateral closure is contrary to international law. Iran disputes elements of this framework, arguing that its own territorial-sea laws take precedence. The counter-position, held by the United States and most of the international community, is that transit passage cannot be suspended unilaterally. The US Navy is the only force capable of enforcing that position at scale.

Resolution is underway. The Islamabad Memorandum, signed 17 June 2026, requires Iran to reopen the strait toll-free for 60 days. As of mid-June 2026 only a handful of ships have transited; analysts estimate roughly four months to full normalization. The live status is at Is the Strait of Hormuz open?, the reopening timeline at When will the strait reopen?, and the full diplomatic record at Peace talks timeline.