"In fact, it [a CSTO air defense system] has been created, created at the bilateral level. We have an agreement and air defense systems with each of the states. This includes Armenia, Kazakhstan, Kyrgyzstan, Tajikistan, and, naturally, Belarus," Shoigu told Rossiya 1 reporter Pavel Zarubin.
The system is "equipped and working," and there are exercises held to maintain it in combat condition, he said, adding that the system will be created de jure if necessary.