A legal expert specializing in international law, Nele Matz-Lück, stated that the sea blockade in the Strait of Hormuz maintained by the United States is “clearly illegal under international law” when it targets neutral shipping alongside military objectives. According to Matz-Lück, such a blockade also contradicts the recently agreed-upon ceasefire with Iran and would effectively constitute a resumption of hostilities.
While a blockade targeting Iranian ports could potentially be permissible under the laws of armed conflict, such measures must remain proportionate and cannot obstruct humanitarian deliveries. However, Matz-Lück asserted that actions such as stopping ships that have paid fees to Iran are “clearly illegal under international law” and are not covered by the law of naval warfare.
Overall, the expert views the United States’ actions as politically risky and legally questionable. She believes this indicates a departure from the principles of free navigation, potentially encouraging other nations to adopt similar measures, which could endanger the foundation of the international maritime legal order. The expert also sharply criticized the US rhetoric, calling terms like “economic terrorism”-used by US Vice President J.D. Vance-a lack of legal definition and an example of “imperial power rhetoric”. She noted that this demonstrates a shift away from established international legal standards toward actions driven by sheer power.
