Middle East — 2026-06-16

US Naval Blockade of Iranian Ports to Remain Until Official MOU Signed Friday

BLUFFormal signature is likely by June 21, but Tehran's navigation fee claim and Trump's toll-free commitment are structurally incompatible, ensuring renewed friction within the 60-day technical window.

The US naval blockade of Iranian ports remains in effect pending formal signature of the US-Iran memorandum of understanding, expected Friday in Switzerland, a source familiar with operations told The War Zone 1. CENTCOM has disabled nine vessels and redirected 139 others since April 13, including the MT Settebello on June 9, whose engine room strike killed three Indian crew members 12. Trump posted Sunday authorizing "immediate removal" of the blockade and toll-free opening of the Strait of Hormuz, then said at a Monday press conference the Strait would be "completely opened" by Friday 13. Iran's Supreme National Security Council stated the blockade would lift "immediately and completely" under the MOU, while Iran's Foreign Ministry separately said Tehran would collect fees for navigation services through the Strait 1.

Analysis
The MOU will likely be signed Friday in Switzerland. High confidence follows from convergent public commitments on both sides and the Iranian Foreign Ministry's statement that text is finalized, though no outlet has obtained the document. Signature removes only the blockade's legal trigger: mine clearing and carrier risk reassessment push commercial transit resumption days to weeks beyond the ceremony regardless. Tehran's service-charge framing of navigation fees is incompatible with Trump's toll-free commitment, and that gap will force renegotiation during the 60-day technical window. The framing may also reflect a genuine reading of MOU terms rather than a rhetorical hedge, making Washington and Tehran potential signatories to structurally incompatible versions of the same agreement. Tanker operators and war-risk underwriters need Friday's outcome to decide rerouting and reset insurance premiums, with days-to-weeks of elevated costs at stake if signing slips.

3 sources