The IRGC declared on Wednesday that "not a litre of oil" would pass through the strait of Hormuz. This is the most absolute blockade language of the conflict, completing an escalation from IRGC operational warnings in the first days, through the Foreign Ministry's statement that tankers "must be very careful" — the first diplomatic-level Hormuz threat of the war — to a declaration of total closure.
The IRGC has backed the rhetoric with force. It struck the Marshall Islands-flagged tanker Louise P with a kamikaze drone, publicly naming the vessel and claiming it belonged to the US. It hit the Prima after the vessel ignored warnings about the transit ban. Both attacks were publicly claimed — the IRGC identified each ship, stated its rationale, and took responsibility. Under UNCLOS, attacking civilian merchant vessels is prohibited unless they directly assist military operations. No such claim was made for either vessel.
The declaration has a conspicuous exception: Iran's own crude continues to flow. Since 28 February, 11.7 million barrels of Iranian oil have transited the same strait, all bound for China. A blockade under international law requires impartial enforcement against all vessels. What the IRGC has constructed is not a blockade but a selective interdiction regime — one that punishes states aligned with the US-Israeli campaign while rewarding those providing diplomatic cover. The last time Iran systematically attacked commercial shipping in The Gulf was the 1980–88 Tanker War, which prompted the US to launch Operation Earnest Will, escorting reflagged Kuwaiti tankers under the American flag. No equivalent convoy operation has been announced.
The practical effect is already measurable. Tanker traffic through Hormuz has fallen 90% from pre-war levels. Every major protection and indemnity club cancelled War risk coverage effective 5 March. Kuwait declared force majeure on all oil exports. The declaration formalises what shipping companies had already priced in: the strait is open only to those Tehran permits through.
