Last week, US President Trump declared that he would declare the Strait of Hormuz "US territory" after defeating Iran. He had previously claimed US "ownership" of the waterway, despite parts of its waters belonging to Iran and Oman. Maritime law experts point out that claiming territory is far from easy.
Zhu Ya, a professor of maritime law at City University London, stated that under US law, a presidential declaration or decree alone is insufficient to claim territory; constitutional requirements must also be met. Under international law, annexation violates the UN Charter, and territory, including waters, can only be acquired through agreement or cession. While occupying territory may give the occupying power control of the area, this act itself does not grant legal ownership.
Bohen, a professor of shipping law at Swansea University, believes the possibility of claiming the Strait of Hormuz as US territory is extremely low. Under international law, this could only be achieved if Iran agrees to cede its territorial waters of the strait to the US, a highly unlikely scenario. He speculates that a more realistic option might be a tripartite agreement between the US, Iran, and Oman to open the strait and impose passage fees, but this would also violate international law and the UN Convention on the Law of the Sea. Zhu Ya emphasized that neither Iran nor Oman possesses absolute rights to the Strait of Hormuz; "freedom of navigation takes precedence"—this is a legal principle. The strait is not the property of either party, but sovereign territory, subject to the international maritime navigation regime. He added that military control does not equate to legal ownership.
