Ukraine's increasingly effective campaign of deep strikes inside Russian territory may be exposing a growing weakness in Moscow's air defenses, with intelligence assessments suggesting the country is running low on a key category of interceptor missiles, according to a new report.
A CBS News report citing three Ukrainian officials familiar with intelligence estimates detailed that Russia is facing a shortage of S-300 interceptor missiles, a Soviet-designed surface-to-air defense system that has long been a cornerstone of the country's layered air defense network.
The reported depletion comes as Ukraine ramps up long-range attacks against military and strategic infrastructure far beyond the front lines, forcing Russia to expend valuable interceptor missiles at a pace that may be difficult to sustain.
While Russia has increasingly relied on newer systems such as the S-350, S-400, and Pantsir-S1 to defend against incoming threats, the S-300 remains a significant component of Moscow's defenses against Ukrainian drones and missiles.
Ukrainian officials told CBS News that intelligence assessments indicate a "reduction in Russia's stockpile of S-300 surface-to-air missiles," although they did not disclose current inventory levels. Previous estimates cited by The New Voice of Ukraine suggested Russia possessed more than 400 interceptors for its S-300PM and S-400 systems in 2025.
Two Ukrainian officials told the outlet that Moscow has increasingly repurposed S-300 missiles for offensive operations against Ukraine. Originally designed to intercept aircraft and missiles, some of the weapons have been modified to function as surface-to-surface missiles, supplementing Russia's arsenal alongside systems such as the Iskander-M and Kinzhal ballistic missiles.
At the same time, Ukraine's rapidly evolving drone campaign has forced Russian air defenses into near-constant action. Kyiv has deployed increasingly sophisticated long-range drones, including jet-powered variants capable of flying farther and faster than earlier models.
Relatively inexpensive drones can force Russia to expend interceptor missiles that are significantly costlier. One Ukrainian intelligence official told CBS News that Russia is struggling to obtain key components needed for missile production, including guidance seekers and control modules.
Western sanctions and export restrictions have complicated Moscow's efforts to acquire advanced technologies from foreign suppliers, the official said. Oleh Chornyi, acting head of Ukraine's Defense Intelligence Directorate (GUR), told CBS News that Russia is prioritizing production of missiles for its newer air defense systems to counter Ukraine's expanding drone attacks.
Kyiv has repeatedly warned Western allies that it is running short of American-made PAC-3 interceptors used by Patriot air defense systems, considered the most effective protection against Russian ballistic missile attacks. The imbalance could become even more pronounced in the future.
As Ukrainian President Volodymyr Zelenskyy met with G7 leaders this week, Ukrainian drones struck an oil refinery deep inside Russian territory, underscoring Kyiv's growing ability to reach targets far from the battlefield. "This time, the Moscow region felt the reach of 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 important components of such pressure."
