UN Convention on the Law of the Sea

The UN Convention on the Law of the Sea (UNCLOS) is the international treaty framework governing maritime rights, including the principle of “transit passage” through straits used for international navigation. Under UNCLOS, states cannot suspend transit passage through international straits — a provision Iran violated by closing the Strait of Hormuz. Iran argued its actions were justified by US/Israeli aggression and the principle of self-defense. The Iranian Cargo Ship Seizure by the US was also argued by Iran to violate UNCLOS provisions on freedom of navigation. The legal conflict between UNCLOS obligations and the actions of both parties formed a backdrop to the UN Security Council debates in which China and Russia vetoed resolutions calling for freedom of navigation.

Connections

• Strait of Hormuz — the strait whose closure violated UNCLOS transit passage rights
• Iran IRGC — violated UNCLOS by imposing the Toll Booth System and closure
• International Response — UNCLOS invoked by Western states in UN proceedings
• Iranian Cargo Ship Seizure — raised UNCLOS counter-arguments by Iran