CENTCOM Enforces Full Maritime Blockade of Iranian Ports Starting 10 a.m. ET, April 13

In a dramatic escalation of the ongoing U.S.–Iran conflict, U.S. Central Command (CENTCOM) began enforcing a naval blockade of all maritime traffic entering and exiting Iranian ports on April 13, 2026, at 10 a.m. ET (14:00 GMT / 6 p.m. Gulf Standard Time). The action follows the collapse of U.S.–Iran talks mediated in Islamabad, which lasted close to 20 hours before JD Vance announced failure to reach agreement on April 12.

The blockade applies to vessels of all nations — regardless of flag or ownership — entering or departing Iranian ports and coastal areas, including all Iranian ports on the Arabian Gulf and Gulf of Oman. CENTCOM clarified that U.S. forces will not impede freedom of navigation for vessels transiting the Strait of Hormuz to and from non-Iranian ports — a critical distinction that attempts to keep global shipping lanes partially functional.

The announcement triggered an immediate market reaction: WTI crude rose nearly 9% and Brent was almost 8% higher in early Asian trade on Monday morning. Oil prices crossed the $100-per-barrel mark again following the blockade announcement, adding inflationary pressure to global logistics costs.

Three Gulf-bound tankers aborted their Strait of Hormuz transits around the time news broke. On Saturday prior, three Chinese-registered VLCCs — the Cospearl Lake, He Rong Hai, and the Liberian-flagged VLCC Sefiros — successfully exited the Gulf via the Iranian-approved route north of Larak Island. All mariners are directed to monitor Notice to Mariners broadcasts and contact U.S. naval forces on bridge-to-bridge channel 16 when operating in the Gulf of Oman and Strait of Hormuz approaches.

Iran’s armed forces described the blockade as an ‘illegal act and amounts to piracy.’ The UK confirmed it will not participate in the blockade but is working to assemble a coalition with France and others to ensure passage through the waterway. CENTCOM Admiral Brad Cooper stated that the U.S. has begun establishing a new passage and will share the safe pathway with the maritime industry to encourage the free flow of commerce.