WASHINGTON—On July 25, Ukraine struck an Iranian cargo ship in the Caspian Sea, killing a sailor in the attack. At the time, Ukraine stated that the ship was carrying military equipment to Russia, while Iranian officials claimed it was a commercial ship and warned Kyiv of reprisal. In the days that followed, Tehran reportedly considered carrying out a retaliatory strike, until Iranian Foreign Minister Abas Araghchi spoke with his Ukrainian counterpart, Andrii Sybiha, easing tensions.
The incident does not come as a complete surprise. Since the start of Russia’s full-scale invasion of Ukraine in 2022, Moscow and Tehran have utilized the Caspian Sea to smuggle weapons, drone-related technology, and sanctioned oil, away from international scrutiny. Meanwhile, Ukraine has sought to disrupt the flow of military supplies to Russia by targeting key logistics networks and transportation routes.
While Araghchi has since said that Sybiha described the strike as “unintentional,” and both parties have stated that they do not seek further escalation, the incident brings attention to the ways in which the wars in Ukraine and Iran are intertwined. Illicit smuggling in the Caspian Sea is just one element of a broader Russia-Iran partnership spanning drone production and innovation, intelligence sharing, and sanctions evasion, creating increasingly direct links between the war in Ukraine and conflicts in the Middle East.
Russia learned sanctions evasion methods from Iran.
At the beginning of the full-scale invasion, Iran shipped hundreds of drones to Russia, primarily Shahed-type models, used as one-way attack drones. Moscow’s intention was apparently to overwhelm Ukraine’s air-defense systems with the low-cost drones. By June 2023, Iran was assisting Russia in the construction of a drone manufacturing facility in Yelabuga to domestically produce Shaheds, which were later rebranded as Geran-2s, following a $1.7 billion deal. Since February 2022, Russia has used an estimated 57,000 Shahed-type drones in its invasion, making them a key component of the Kremlin’s battlefield strategy.
As the war progressed, Russia refined and modified the Shahed design, and it is now returning the favor by giving Iran more advanced drones. Following US-Israeli strikes in February this year, senior Iranian and Russian officials conducted secret talks throughout March for drone transfers. The new modifications are reportedly wide-ranging and include jet engines, cameras for reconnaissance, radio links, artificial intelligence–computing platforms, Starlink-enabled internet devices, and advanced anti-jammers. While little is public about the shipments, Western officials reportedly believe that Iran has utilized improved Russian drone systems in the Middle East and suspect that some modified drones were deployed in Iran’s recent strike on US assets in Riyadh.
Recent Russia-Iran military cooperation extends well beyond drones. It also has included, for example, the formation of commissions and working groups to share defense practices, as well as shipments of ammunition and artillery shells from Iran to Russia. In 2023, Iran reportedly shipped more than 300,000 artillery shells and a million rounds of ammunition over six months.
In March of this year, The Washington Post reported that Russian officials were providing Iran with intelligence to target US forces in the Middle East, passing on the location of warships, aircraft, and other US military assets to their Iranian counterparts. Iran itself possesses few military-grade satellites, making Russia’s advanced capabilities increasingly beneficial to its military operations across the Gulf. More recently, Ukrainian President Volodymyr Zelenskyy pointed to evidence of correlations between Russian satellite activity and subsequent Iranian strikes on US assets.
In the economic sphere, Russia’s war on Ukraine catalyzed new Tehran-Moscow collaboration on sanctions evasion. Previously, bilateral economic engagement was a point of tension between Iran and Russia, but the invasion and subsequent Western sanctions on Russia increasingly aligned the two countries’ strategic economic goals. Russia learned sanctions evasion methods from Iran, including the use of shadow fleet tankers to export oil to China, while Iran provided Russia with critical industrial components for its war that it could no longer legally import.
The sanctions evasion network—in which China also plays a large role—allows Russia and Iran to sell their sanctioned oil and purchase dual-use or military technology. These evasion mechanisms are more resistant to Western sanctions and export controls, allowing both countries to rebuild their arsenals and bring in much-needed revenue.
To be sure, Russia’s support of Iran has fallen short of what many in the Iranian regime would have preferred following Operation Epic Fury, reaffirming the practical and opportunistic nature of their partnership. In June, Russian President Putin insisted to an audience in St. Petersburg that Iran “did not ask” Russia for any weapons, and “we did not supply any armaments to Iran.” His comments exposed the limits of Moscow’s commitment to Tehran: Russia remains more concerned with its own war effort in Ukraine, its relationships with other regional partners, and avoiding direct confrontation with Western powers.