THE HAGUE, Netherlands — Updating the Chemical Weapons Convention for the first time, the Organization for the Prohibition of Chemical Weapons agreed Wednesday to ban the nerve agent Novichok, which was used in the attempted assassination last year of a former Russian double agent.
Other banned substances include sarin, ricin and sulfur mustard. The convention came into force in 1997.
Read the Top 8
Sign up for the Top 8, a roundup of the day's top stories delivered directly to your inbox Monday through Friday.