Russia's full-scale invasion of Ukraine has fundamentally reversed the military relationship between Moscow and Tehran, turning Iran from a decades-long arms buyer into a net supplier of weapons to Russia. The transformation is detailed in a new Foreign Affairs analysis by three Carnegie scholars, "Hvylya" reports.

For decades, the arms trade flowed in one direction. Throughout the 1990s and early 2000s, Russia delivered MiG-29 fighters, Su-24 strike aircraft, Kilo-class diesel submarines, T-72 tanks, and S-200 air defense systems to Iran. Later came Tor-M1 short-range air defense batteries and the S-300 long-range surface-to-air missile system. But these transfers "never constituted alliance-level military integration," analysts Alexander Gabuev, Nicole Grajewski, and Sergey Vakulenko write. Deliveries were episodic and excluded the most powerful systems, such as the S-400 or the most advanced fighter jets.

The 2022 invasion changed everything. Iran's most consequential contribution was the Shahed series of loitering munitions, which Russian forces began deploying in autumn 2022 to supplement dwindling precision-missile stocks. Moscow moved quickly to localize production, "redesigning internal components to accommodate domestic supply chains and sanctions-constrained electronics and scaling output well beyond what Iran had originally supplied."

In return, Russia provided Iran with new military hardware, including Yak-130 trainer jets, Mi-28 attack helicopters, dozens of Spartak armored vehicles, and small arms, according to media reports. Iran also signed contracts for Su-35 fighter jets and portable air defense systems, though their delivery status remains unclear.

Beyond hardware, Russia helped Iran gain diplomatic standing. In 2023, the Kremlin pushed to make Iran a member of the Shanghai Cooperation Organization. Moscow then lobbied for Tehran's inclusion in the expanded BRICS and orchestrated a free-trade agreement between Iran and the Eurasian Economic Union. The Kremlin has also shown willingness to engage with Iranian proxies, particularly the Houthis, by providing them with training and weapons.

Yet the partnership has exposed a bitter irony: now that Iran faces its gravest military crisis, Russia cannot reciprocate. The advanced fighters, air defense systems, and precision munitions Iran desperately needs are the same assets Russia is burning through in Ukraine.

Also read: "This Is the Final Battle": Iran Expert Reveals Why Tehran Refuses to Capitulate.