Russia’s Oreshnik IRBM, exceeding Mach 10, delivers MIRVs with submunitions, making interception difficult.

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.

Russian President Vladimir Putin said in a televised address that the attack was a test of Russia's "newest missile," an IRBM called "Oreshnik."

Russia named the missile the Oreshnik, or hazel tree, and said it is impossible to intercept it with air defenses.

President Vladimir Putin said Friday that Russia will continue to test and start mass-producing the hypersonic ballistic missile that it fired at Ukraine Thursday.

This is the first time Russia has used its so-called Oreshnik intermediate-range ballistic missile in combat. The launch also serves as a warning to the West.