Camilla Jessen
The European Union is preparing to formally accuse Russia of violating international law by using chemical weapons.
The European Union is preparing to officially accuse Russia of using chemical weapons during its war in Ukraine.
A new draft sanctions document—seen by Radio Liberty’s Sistema project—says Russia used CS tear gas in combat, which is banned under international law.
This is the first time the EU has made such an accusation.
Evidence from Chemical Weapons Watchdog
The EU’s claims are based on reports from the Organisation for the Prohibition of Chemical Weapons (OPCW), published in November 2024 and February 2025, at Ukraine’s request.
These reports looked into two suspected attacks near the villages of Maryivka and Ilyinka in the Dnipropetrovsk region.
Investigators found traces of CS gas in soil and water samples.
Ukrainian soldiers also gave statements about what they experienced, and photos showed remains of RG-Vo grenades, which are made in Russia and labeled as containing poison.
Russian state media previously showed footage in 2024 of these same grenades being used in battle.
Ukraine’s Defense Ministry also said that Shahed-type drones, used by Russian forces, have been found with CS gas capsules inside.
This suggests Russia may be using drones to deliver tear gas.
Why This Is a Violation
CS gas—also known as “Lilac”—is usually used by police to control riots.
But using it in war is banned by the Chemical Weapons Convention (CWC).
The CWC says no chemical, even if not deadly, can be used as a weapon in war.
CS gas causes strong burning in the eyes, nose, and lungs, and can lead to breathing problems, pain, and disorientation.
The EU Council explained its reasoning for the new sanctions, saying:
Because of the serious situation and Russia’s failure to explain the use of tear gas, the EU wants the OPCW to find out who is responsible.
The EU’s new sanctions would target parts of the Russian Defense Ministry connected to chemical weapons.
This includes the Radiation, Chemical, and Biological Defense Troops and the 27th and 33rd Research Centers, which are involved in developing and possibly using banned substances.