Although Russia is in the midst of replacing Cold War era RS-18 (SS-19) ICBMs with the new solid fuel RS-24 it test fired a new RS-28 missile in late October. The RS-28 is meant for is the new hypersonic glide vehicle project Russia announced in 2013
Russia believes the RS-28 is essential for state security because it can carry nine or more independently targeted warheads and will be the most important weapon in its ICBM arsenal. Moreover the missile RS-28 is replacing (R-36M) is aging to the point where refurbishment is no long able to keep these four decade old missiles operational.
The country’s Tactical Missiles Corporation believes the weapon will be so fast it will be virtually impossible for current defense systems to knock it out of the skies.
SOURCES- Strategy Page, The Sun UK