Middle East — 2026-08-18

Iran-US 60-Day MOU Expires as Iran Threatens Shift to Fully Offensive Posture in Strait of Hormuz

BLUFIran's convergence of declared offensive posture, IRGC readiness signals, and collapsed Hormuz traffic likely produces an attack on shipping or a US asset within three weeks, risking a broader Gulf escalation that would disrupt global oil transit.

The 60-day US-Iran memorandum of understanding, signed in Islamabad on June 17, expired Monday with President Trump indicating in the Oval Office he would not seek an extension 1. A senior Iranian official told Reuters Tehran has shifted to a "fully offensive" posture and set a deadline of a few weeks for Washington to implement the MoU's provisions, with escalation across the Strait of Hormuz threatened if diplomacy fails 2. IRGC political bureau chief Yadollah Javani said Sunday Iranian forces were ready to take "whatever action is needed," warning of "strategic surprises," while army spokesman Mohammad-Reza Akraminia said any US landing on Iran's islands would be met with force 3. Kpler data show Hormuz vessel traffic fell 64% from its post-MoU peak to single digits by mid-August, with only three ships transiting Sunday and roughly 520 vessels backed up in the Arabian Gulf 4.

Analysis
Iran's shift to a declared "fully offensive" posture with a fixed weeks-long deadline, paired with Hormuz traffic collapsing to single-digit daily crossings, likely produces an Iranian attack on a commercial vessel or US military asset in or near the strait within the next three weeks. High confidence reflects three converging indicators: senior-official confirmation of the policy shift, IRGC and army leadership publicly signaling readiness for offensive action, and vessel-tracking data showing operators already treating the corridor as unsafe. The Kharg Island and southern-island defensive buildups indicate Tehran is postured for retaliation against any US landing attempt, not only shipping interdiction. Roughly 520 vessels remain backed up in the Arabian Gulf, giving Iran a dense target set if diplomacy collapses at the deadline.
5 sources
  1. Trump indicates US won't seek memorandum of understanding extension following conclusion of 60-day ceasefire - Washington Examiner
  2. Iran has shifted to 'fully offensive' policy - Reuters - Iran International
  3. Iran signals readiness for 'US ground operations' as strategy shifts gear - Al Jazeera
  4. Hormuz traffic falls to single digits as 60-day deadline for US-Iran MoU expires - The National
  5. Iran Threatens to Go on Offensive in Strait of Hormuz if Diplomacy With US Fails - Reuters

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