The Sea that is not a Sea - Why the Legal Status of the Caspian Sea matters in the Russian War against Ukraine
The international law of the sea regulates the global ocean, that is, the totality of all seas and oceans that are connected with each other, even if only through narrow connections, such as the Black Sea that is connected to the Mediterranean through the Turkish Straits and the Mediterranean, that is connected to the oceans only through the Strait of Gibraltar and the (artificial) Suez Canal. Without a doubt, the Black and Mediterranean Seas are covered by the international law of the sea. Seas that are not connected to the global ocean are not covered by the international law of the sea and are instead, at least legally speaking, large lakes rather than seas. This is also the case for our planet’s largest lake, the Caspian Sea. Despite the name in the English language, the Caspian Sea is not a sea within the meaning of the international law of the sea. The United Nations Convention on the Law of the Sea and customary international law of the sea, therefore, do not apply to the Caspian Sea. Instead, an international legal order of its own applies to the Caspian Sea and the legal community that is formed by its littoral states.
This has consequences in the current war waged by the Russian Federation against Ukraine because the presence of the Caspian Sea and its particular legal status facilitate the transport of weapons from the Islamic Republic of Iran to Russia while it is impossible for non-littoral states to take action aimed against the proliferation of weapons (including potentially weapons of mass destruction) between Russia and Iran. On the high seas, significant efforts have been underway in the last decades to combat such proliferation. This is done within the framework of the existing international law of the sea that allows military vessels to conduct visits of suspicious vessels under certain circumstances, for example, to combat weapons or drug smuggling. Especially when sanctions have been imposed by the Security Council of the United Nations, such visits are an essential aspect of coordinated efforts to enhance international security. Russia is a permanent member of the United Nations Security Council and enjoys veto power, making it practically impossible for the Security Council to impose sanctions against Russia or its leaders. International efforts to combat arms trafficking to Russia will only be possible beyond the framework of the Security Council and will meet similar legal challenges to the Proliferation Security Initiative.
But in the Caspian Sea, such efforts to halt arms trafficking are legally impossible for non-littoral states. The practical consequence is that the littoral states Russia and Iran, although they do not share a land border, have an easy way to transport weapons and other goods to exclude states that are not littoral states of the Caspian Sea. The practical result is that Russia and Iran can act as if they would have a direct land border. This facilitates the delivery of weapons from Iran to Russia that are being used to attack the civilian population of Ukraine in Russia’s illegal war of aggression.