Russia says it has tested yet another new reentry vehicle design on an RS-12M Topol intercontinental ballistic missile, or ICBM. The development comes amid persistent complaints about America’s ballistic missile defense shield, as well as renewed tensions between the Kremlin and the U.S. government over various agreements limiting the development of nuclear weapons.

On Dec. 26, 2017, the Russian Strategic Missile Force fired a Topol with the “perspective [sic] armament” from the Kapustin Yar range in the Astrakhan Region near the border with Kazakhstan, state-run media outlet TASS reported. The Kremlin did not say how far the test missile flew, where it landed, or whether the experiment had been a success.