Russia says the 9M730 Burevestnik (Storm Petrel) - dubbed the SSC-X-9 Skyfall by NATO - is "invincible" to current and future missile defences, with an almost unlimited range and unpredictable flight path.

With unlimited range and near-absolute stealth, the Burevestnik 9M730 missile not only changes the game in the arms race but also poses a major challenge to modern air defense systems in the world.

President Vladimir Putin said on Sunday that Russia had tested its Burevestnik nuclear-powered cruise missile. Here are some key facts about the weapon.

"We can confirm that Russia has conducted a new test launch of the long-range cruise missile Skyfall (Burevestnik) on Novaya Zemlya," Vice Admiral Nils Andreas Stensoenes, head of Norway's Intelligence Service, told Reuters in an emailed statement.