Press releases, 26.02.2024

Switzerland takes note of the fourth report of the Investigation and Identification Team of the Organisation for the Prohibition of Chemical Weapons (OPCW), which has been working to identify the perpetrators of chemical weapons use in Marea, Syria on 1 September 2015. Switzerland condemns the use of chemical weapons in the strongest terms and calls on all parties to the conflict in Syria to refrain from using them and comply with their obligations under international humanitarian law. Those responsible for crimes under international law in Syria must be held accountable.

The fourth report of the OPCW's Investigation and Identification Team (IIT), which was published on 22 February 2024, sets out the findings from the investigation into the use of chemical weapons in Marea, 25 kilometres north of Aleppo. The report concludes that there are reasonable grounds to believe that units of the terrorist group Islamic State in Iraq and the Levant (ISIL) deployed sulphur mustard as part of an attack to capture the town of Marea. The IIT notes that several artillery projectiles were fired at Marea on the morning of 1 September 2015, with no discernible targeting pattern. Upon impact, at least six projectiles fired from areas under the control of ISIL leaked a black, viscous substance. Some 11 individuals who came into contact with the substance experienced symptoms consistent with sulphur mustard exposure.

Switzerland, which is represented at the OPCW by Ambassador Corinne Cicéron Bühler, condemns this deployment of chemical weapons in the strongest terms. The ban on the use of chemical weapons is binding on all parties to conflicts at all times and in all circumstances. Switzerland calls on all parties to the conflict in Syria to respect international law and in particular international humanitarian law. Those responsible for the use of chemical weapons must be held accountable. As an elected member of the UN Security Council, Switzerland works to ensure compliance with international law. It is committed to strengthening the International Criminal Court, fighting impunity for the most serious crimes, and protecting civilians and other war victims.

The IIT has been receiving political and financial support from a large number of countries, including Switzerland, for many years. Switzerland has made a special contribution to the work of the OPCW through the Spiez Laboratory, which received the OPCW–The Hague Award for its services in November 2023. As well as supporting investigations into chemical weapons use, Switzerland is committed to preventing the manufacture of chemical weapons and is therefore involved in work to apply effective export controls. Switzerland also supported the decision of the last OPCW Conference of States Parties in November 2023, which recommended, among other things, that the member states of the Chemical Weapons Convention (CWC) adopt measures to prevent the transfer of goods for chemical weapons manufacture to unlawful recipients in Syria. The fact that a non-state actor has been identified as the perpetrator of the 2015 chemical weapons attack on Marea underlines the need for these measures.

Switzerland will continue to provide humanitarian assistance to the people affected by the conflict in Syria as well as to neighbouring countries which have taken in the majority of those displaced. In addition, it will continue to offer its good offices to facilitate a lasting peace in Syria. A key element of this is its support for the UN peace process in Geneva.

Further information:

2023 OPCW-The Hague Award
Fourth report of the OPCW's Investigation and Identification Team

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