Russia has reportedly deployed a missile defense system near its border with North Korea.

Foreign media, including Reuters, quoted the chief of Russia's general staff, Nikolai Makarov, on Wednesday as saying that Russia has deployed S-400 surface-to-air missile systems in the Far East to counter the potential threat posed by North Korean missile tests.

Makarov told reporters in the Mongolian capital of Ulaanbaatar that Russia is definitely concerned by the conditions under which tests are being carried out in North Korea, including tests involving nuclear devices.

The S-400 is Russia’s most sophisticated missile system and is designed to intercept and destroy airborne targets at distances of up to 400 kilometers. The system is also capable of destroying stealth aircraft, cruise missiles and ballistic missiles.