The S-550 missile defence system 'has entered combat duty', according to defence sources who spoke to state news agency TASS on Wednesday.
While little is known about the missile, it is thought to be Russia's latest foray into the space arms race - designed to take out targets hundreds of miles above earth such as low-orbit satellites, nuclear warheads, and orbital hypersonic weapons.
Moscow is thought to have carried out a test of this weapon system last month when it blew up one of its own defunct spy satellites in a move that enraged Washington and ramped up tensions with NATO.
Vladimir Putin has been rapidly bulking up his armed forces as he takes a more aggressive stance in eastern Europe, pressures NATO to sign off on new security guarantees for Moscow, and forges alliances with China.
Russian currently has up to 100,000 troops stationed along the Ukrainian border amid warnings from the Pentagon that an invasion could take place within weeks.