The Pentagon says the Oreshnik is a tweak of Russia’s RS-26 Rubezh missile, an intercontinental ballistic missile (ICBM) that has been tested since 2011.

Russia has launched the experimental Oreshnik missile as a strategic message to the world following the West's approval of Ukraine's use of long-range weaponry for strikes deep within Russia. Source: European Pravda,

STORY: On Nov. 21 Russia struck Ukraine's Dnipro with a new kind of missile.Known as Oreshnik, or hazel tree in Russia, it caused limited damage, according to senior officials. But the first combat use of such a design – which Russian President Vladimir Putin called unstoppable – has drawn scrutiny from Western military experts.