Russia has destroyed the last of the massive chemical weapons stockpile it inherited from the Soviet Union at the end of the Cold War, the Organisation for the Prohibition of Chemical Weapons (OPCW) says. The final artillery projectiles filled with VX nerve agent were dismantled on Sept. 27 at a facility in Russia’s Udmurtia region, wrapping up an effort that spanned two decades. “The completion of the verified destruction of Russia’s chemical weapons program is a major milestone,” says Ahmet Üzümcü, OPCW’s director general. OPCW oversees global efforts to eliminate stockpiles under the Chemical Weapons Convention, which took effect in 1997. The group says that over 96% of declared stockpiles have been eliminated by its 192 member nations. Russia declared an arsenal of 39,967 metric tons of chemical warfare agents, including mustard agent, phosgene, and the nerve agents sarin, soman, and VX. In 2012, the U.S. said it had destroyed 90% of its declared chemical weapons, about 30,500 metric tons. But budget shortfalls have slowed the disposal program, and the last of the U.S. stockpile is not scheduled for elimination until 2023.