 Aziz Karimov/Getty ImagesTHE NEWS Western efforts to stop the flow of Iranian weapons into Russia for use in Ukraine are running into a 3,300-foot-deep problem: the Caspian Sea. American officials told Semafor that Tehran has stepped up its movement of arms to Moscow via the landlocked body of water — often described as the world’s largest lake — which has prevented interdiction efforts by putting shipments beyond the reach of U.S. and NATO naval power. The U.S. has successfully intercepted seabound shipments of Iranian weapons to other war zones, such as Yemen. The Central Asian countries that border the Caspian, Azerbaijan, Kazakhstan, and Turkmenistan, have been reluctant to join the West in enforcing sanctions on Russia over Ukraine, according to U.S. officials, let alone interdict arms shipments. Without those governments’ cooperation, American and NATO forces can’t legally police their territorial waters. “In terms of international law, you’re not going to have anyone there on your side,” said Benham Ben Taleblu, a senior fellow at the Foundation for Defense of Democracies in Washington. “In terms of political will to do something risk tolerant and using a local actor, we also are not going to have anyone there.” KNOW MORE In recent weeks, the Biden administration has called Tehran “Russia’s top military backer” in Ukraine and said the U.S. is following ongoing shipments of kamikaze drones, artillery, and tank rounds from Iran to the Russian military. The Kremlin, in turn, has pledged to provide Iran with “unprecedented” military support in the form of Sukhoi fighter jets, Russian attack helicopters, and S-400 air defense systems. Russian President Vladimir Putin and his Iranian counterpart, Ebrahim Raisi, also signed an agreement last month to build a North-South transportation corridor to better connect their countries and economies, and to grow trade with the other Caspian Sea nations. The corridor will buttress the maritime links between Russia and Iran through the construction of rail lines running adjacent to the Caspian, through Azerbaijan and other former Soviet states. It’s part of the broader effort by Moscow and Tehran to circumvent the growing sanctions wall being constructed against them by the U.S. and European Union, said Iran and Russia analysts. The two countries have developed direct banking channels to operate outside the SWIFT payment system that governs global financial transactions. The Caspian Sea routes can shield their direct arms shipments. JAY’S VIEW The war in Ukraine is accelerating a splintering between Western and Eastern economies, with Russia increasingly shielding itself behind China, Iran, and the former Soviet states. But the Caspian Sea is the most physical manifestation of this global breakdown, and the Kremlin’s ability to hide. The Biden administration said it first began detecting Iranian drone shipments to Russia last summer, including through air deliveries. But private companies, such as Lloyd’s List in London, said they also began picking up at this time an unusual trend in the Caspian Sea — trade involving Russian and Iranian ships was spiking while many of their deliveries were being made with their Automatic Identification System signals turned off. The United Nations requires most maritime traffic to use AIS transceivers to track their movements in international waters. “There are several reasons for ships to switch off AIS, including transmission or safety issues, but it is commonly used as a tactic to obfuscate journey origins and destinations, as well as other illicit activity,” Lloyd’s List wrote in a report about this dynamic in the Caspian Sea. The most traveled routes involving these shipments were the Russian port of Astrakhan and Iran’s Amirabad port. The Wall Street Journal reported in April that Russian ships had ferried 30,000 artillery shells and a million rounds of ammunition from Iran to Russia via the Caspian Sea during the previous six months, citing data from Middle Eastern governments. The Biden administration has sought to break up the Russian-Iranian trade through a wave of sanctions targeting the companies, procurement networks and ships and airplanes engaged in this trade. In April, the Treasury Department sanctioned six entities supporting Iran’s drone production, including companies in China and Malaysia. But the Caspian Sea is a blind spot in this counter-proliferation strategy — a place where the U.S. can’t patrol, and local governments are disinterested in helping. ROOM FOR DISAGREEMENT The Russian and Iranian governments didn’t respond to requests for comment from Semafor concerning their alleged use of the Caspian Sea to ship arms. But Russian and Iranian leaders have said in recent months that their development of the North-South Trade Corridor was solely focused on growing the region’s economies and creating an alternative trade route to the Suez Canal. “The unique North-South transport artery, of which the Rasht-Astara railway will become a part, will help to significantly diversify global traffic flows,” Russian President Vladimir Putin said on May 17. NOTABLE | 
