Statement from Minister of State for the Middle East, following publication of a report from the Organisation for the Prohibition of Chemical Weapons (OPCW) which finds Daesh responsible for 2015 sulphur mustard attack in Marea

The Minister of State for the Middle East, South Asia, UN and the Prime Minister’s Special Representative on Preventing Sexual Violence in Conflict, Lord (Tariq) Ahmad of Wimbledon has condemned Daesh use of chemical weapons in Syria, following the publication of an OPCW report which found that Daesh fighters are responsible for a chemical weapons attack using sulphur mustard in Marea in the Syrian Arab Republic in September 2015:

We commend the Organisation for the Prohibition of Chemical Weapons (OPCW)’s Investigation and Identification Team (IIT) for its expert and independent analysis which has found Daesh was responsible for the use of chemical weapons on civilians in Marea in 2015. The IIT have shown consistent resilience and professionalism in attributing responsibility in cases of both state and non-state actors use in Syria. They have our full support.

This report adds to the shocking track record of Daesh use of chemical weapons. The OPCW-UN Joint Investigative Mechanism previously found Daesh responsible for three other attacks in Marea in 2015 and in Umm Hawsh in 2016. We condemn all use of chemical weapons during the Syrian conflict perpetrated by Daesh and the Assad regime. UN and OPCW mandated investigations have found the Assad regime responsible for at least nine chemical weapons attacks including using sarin and chlorine.

The international community should be gravely concerned about the threat of non-state actors developing, acquiring, and using chemical weapons. The proliferation risk in Syria has only been exacerbated by instability in the region. We urge all States Parties to the Chemical Weapons Convention to cooperate to implement the Decision on ‘Addressing the Threat from Chemical Weapons Use and the Threat of Future Use’ adopted in November 2023, which expressed concern about use by state and non-state actors in Syria.

This is the fourth report by the OPCW’s Investigation and Identification Team (IIT) into chemical weapons attacks in Syria. Following a rigorous and independent analysis of the evidence, the OPCW’s report has concluded that there are reasonable grounds to believe that units of Daesh were the perpetrators of a chemical weapons attack using sulphur mustard on Marea on 1 September 2015 in the Syrian Arab Republic.

Previous reports from the OPCW’s IIT had found the Assad regime responsible for attacks on Saraqib and Douma in 2018 using chlorine, and three separate attacks with sarin and chlorine in Ltamenah in March 2017. All use of chemical weapons is prohibited under international law.

The United Kingdom is determined that those responsible for chemical weapons attacks should be identified and held to account. As well as our support to the OPCW, the UK has imposed sanctions under the UK’s Syria Sanctions regime and Chemical Weapons Sanctions regime on 32 individuals and 7 entities previously identified for their involvement in Syria’s chemical weapons programme. Designated persons are subject to asset freezes and travel bans.

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Published 26 February 2024