July 12, 2019 "Information Clearing House" -  On July 4, the government of Gibraltar detained in its waters a Panamanian ship, the Grace I, allegedly on its way to deliver Iranian oil to a Syrian harbor. Immediately after the move, Gibraltar outlined in an official statement that the “action arose from information giving […] reasonable grounds to believe that the vessel, the Grace I, was acting in breach of European Union sanctions against Syria.” And it added: “We have reason to believe that the Grace I was carrying its shipment of crude oil to the Banyas Refinery in Syria.” One day later, the Gibraltar Supreme Court issued an order confirming that the detention of the Grace I for another 14 days was required “for the purposes of compliance with the EU Regulation 36/2012 on sanctions on Syria.”

On what grounds could a European government detain a non-European vessel transporting to Syria crude oil extracted by a non-European country, Iran?

The European Union firmly condemns the principle of secondary, or extra-territorial sanctions, widely practiced by the United States. Therefore, European prohibitions address primarily European nationals as well as persons and entities active on European territory. European law cannot prohibit a Panamanian ship from carrying what it wishes in open seas (except, of course, products targeted by international law, like drugs or undeclared nuclear materials). However, it can forbid European insurance companies from insuring a ship or its freight, it can forbid European banks from financing the venture, it can detain the ship if it stops in a European harbor, it can forbid the freight from being brought ashore. But for this, the ship itself, its freight, or its destination must be subject to European sanctions.