Deep strikes in Ukraine leave Russia short of air defense missiles, possibly at “inappropriate levels”

Kyiv – Russia is running out of a key type of missile interceptor, sources tell CBS News, which may help Ukraine launch effective strikes deep into Russian territory as analysts note a possible shift in favor of Kyiv more than four and a half years into the war.

Moscow is facing a shortage of S-300 missile interceptors, three Ukrainian officials familiar with the country's intelligence estimates told CBS News. The IS-300, a surface-to-air missile system designed by the Soviet Union in the 1960s and 70s, has often served as an important part of Russia's air defense against cruise and ballistic missiles.

Throughout its war in Ukraine, Russia has turned to more advanced interceptors for that purpose, including the new S-350, S-400 and Pantsir-S1 systems. But the S-300s remain part of Moscow's defense against Ukrainian missiles and drones.

By 2025, estimates from Ukrainian intelligence services reported by The New Voice of Ukraine suggested that Russia had more than 400 existing connectors for the S-300PM and S-400 air defense systems.

Ukrainian officials who spoke to CBS News this week did not specify how many Russian interceptors it is believed to still have, but noted “a reduction in Russia's inventory of S-300 surface-to-air missiles,” and suggested several possible explanations.

Although normally used only for air defense, the Russian military recently returned S-300s for offensive strikes in Ukraine, according to two officials. This has meant reconfiguring their trajectory to function as a surface-to-surface missile, complementing other Russian weapon systems such as the Iskander-M and Kinzhal missiles.

Ukraine has also reduced Russia's stock by forcing it to try to block more and more new volleys, skillful dronesincluding some equipped with faster jet engines and flying higher than older models. That led Russia to deploy interceptors it may have reserved for defense against Ukrainian missiles.

Ukraine sought to increase the deficit by targeting Russian air defenses directly, analysts said.

“In the past few months, Ukraine has destroyed or targeted a number of air defense systems in the occupied areas – Crimea, Dniester, Luhansk, and other places,” said Rob Lee, a Russian military expert at the Foreign Policy Research Institute. “Many of Russia's air defense missiles are being used very quickly, at a kind of disproportionate rate, because Ukraine can produce deeper strike drones than Russia, in some cases, to produce air defense missiles.”

Replenishment of stocks may be a challenge in Russia. One Ukrainian official told CBS News that Moscow does not have the necessary materials to build the missiles — including guidance seekers and control modules. The official said that Russia, long under severe sanctions, is experiencing difficulties in obtaining these materials from Western and Chinese manufacturers.

Ukrainian intelligence officials have warned that Russia still has some modern air defense systems capable of defending against strikes.

Moscow is prioritizing the “production of modern air defense missile systems” to counter Ukrainian drone attacks, Oleh Chornyi, acting head of the Defense Intelligence of Ukraine (GUR), told CBS News.

And Ukraine has its own air defense problems. Kyiv has the alarm went off this year due to its shortage of American PAC-3 interceptors, which are Russia's most reliable anti-missile defense systems.

Fabian Hoffman at the Norwegian Institute for Defense Studies estimates that Russia could rapidly increase its production of ballistic missiles to 600 or 800 a year. Lockheed Martin, which makes the PAC-3 interceptors used by Ukraine, delivered only 620 to the world last year.

However, the intelligence analysis suggesting Russia's deficit comes amid a broader assessment of the change instead of Kyiv on the battlefield.

As Ukrainian President Volodymyr Zelenskyy met with G7 leaders in France this week, drones launched by his country struck an oil refinery inside Russia.

“This time, the Moscow region felt that it was reaching Ukraine's long-range capabilities,” Zelenskyy said. “Russia must be forced to end its war against our people, and Ukraine's long-range weapons are one of the key components of such pressure.”