US Central Command has turned its attention to the Caspian Sea as part of its focus on preventing Iran from acquiring advanced weapons and other materials. On November 7, the command established Task Force Iron Gate, an initiative aimed at restricting Iranian weapons transfers across land borders and the inland waterway.
The move highlights the growing strategic importance of the Caspian, which has emerged as an increasingly significant corridor linking Iran and Russia, carrying commercial trade, military equipment and sanctioned goods. Unlike the Persian Gulf, the Caspian is not directly accessible to Western navies.
The Caspian is the world's largest enclosed inland body of water, bordered by Russia, Iran, Azerbaijan, Kazakhstan and Turkmenistan. During the Soviet era, Iran and the Soviet Union were the only two major states on the sea, but the Soviet collapse in 1991 brought newly independent countries to its shores and transformed the region's landscape.
Trade across the sea dates back centuries, including commercial links between northern Iran and Russian ports. In modern times, the Caspian has become part of the International North-South Transport Corridor, a rail, road and maritime network connecting Russia to Iran and onward to Pakistan and India. Iran was investing in the route before the war began in February, seeking to shift its trade toward China and Central Asia as it was cut off from the West.
Russia's key Caspian ports include Astrakhan and Makhachkala, while Iran operates ports such as Bandar Anzali and Amirabad, handling grain, industrial goods and other cargo. The route became more important after Russia's invasion of Ukraine in February 2022, when Western sanctions increased pressure on both Moscow and Tehran.
The waterway has long carried military weight for Moscow. Russia launched strikes in Syria from the Caspian in 2015. In November 2024, Ukrainian Navy spokesman Dmytro Pletenchuk said, "There are also missile carriers in the Caspian Sea that can launch Kalibr missiles," adding that Russian forces enter the water area to set up launch lines for firing at Ukraine, likely to avoid casualties among their own civilians if old missiles were accidentally dropped.
The sea has also become a theater of the war itself. In August 2025, Ukrainian Special Operations Forces struck the Russian cargo ship Port Olya-4, which was transporting military cargo from Iran, in what the website militarnyi.com described as the first confirmed loss of its kind. In September 2026, a report claimed Ukraine may have targeted the Russian warship Tatarstan.
Iranian naval facilities at Bandar Anzali were hit by airstrikes on March 18, 2026, in an attack that appeared to destroy an Iranian Navy corvette, missile boats and several auxiliary vessels. Radio Free Europe noted in April that Israel had launched air strikes on the Iranian naval outpost there, and on July 25 President Volodymyr Zelensky said Ukrainian forces had struck vessels involved in military cargo shipments connected to Iran, as well as a Russian warship. Ukraine dismissed Iranian threats of retaliation at the time.
Weapons have flowed in both directions. Iran shipped more than 300,000 artillery shells and one million rounds of ammunition to Russia across the Caspian in 2023, according to an April 2023 Wall Street Journal report, and also supplied Shahed drones and technology that helped Russia establish domestic drone production. In May 2026, US officials told The New York Times that Russia was sending drone components to Iran through the Caspian, potentially helping Tehran replenish military capabilities following American and Israeli strikes.
Commercial shipping has continued despite the attacks. According to Lloyd's List Intelligence, active Iranian- and Russian-flagged vessels in the Caspian increased 21% year on year in August 2026, while general cargo capacity on the bilateral corridor rose 36%. The route faces limitations including shallow waterways and restricted port capacity. For Washington, the challenge is distinguishing civilian commerce from military shipments and sanctions evasion, and how the new policy will be implemented remains unclear, especially as the administration has sought to improve ties with Moscow and littoral states may be wary of the war spreading to the sea.
