The prohibition against the use of chemical weapons, firmly established in the Chemical Weapons Convention, has been repeatedly breached in the Syrian civil war. After a poisoning using a nerve agent was attempted in Salisbury in 2018, concerns about the erosion of the 'taboo' on chemical weapons use deepened. EU action to counter the re-emergence of chemical attacks culminated in the enactment of a sanctions regime against the use of chemical weapons in 2018 – the bloc's first autonomous sanctions regime that is not country-specific. The sanctions regime is an attempt by the EU to support the multilateral chemical disarmament regime after efforts to frame a response via the United Nations Security Council failed. Concurrently, it represents a balancing act combining support for the norm against chemical weapons use with a reluctance to antagonise Russia.