Russia, alongside the US and China, is one of the few countries known to possess hypersonic weapons.
These are typically described as missiles that travel long distances at breakneck speeds, more than five times faster than the speed of sound (Mach 5).
Unlike conventional ballistic missiles, hypersonic weapons are faster, travel low through the atmosphere and are, consequently, much harder to intercept.
Three years ago, the Russian President claimed during a televised broadcast that one such weapon in Russia’s arsenal, the Avangard missile, was 20 times faster than the speed of sound (Mach 20) and “absolutely invulnerable to any air or missile defence system”.
More recently, Russian officials have confirmed the launch of the Zircon, or Tsirkon, missile from a submarine in the Barents Sea.