136. As the conflict escalates, the potential for use of chemical weapons is of deepening
concern. Chemical weapons include toxic chemicals, munitions, devices and related
equipment as defined in the 1997 Convention on the Prohibition of the Development,
Production, Stockpiling and Use of Chemical Weapons and Their Destruction. Also
applicable is the 1925 Geneva Protocol which Syria has ratified. The use of chemical
weapons is prohibited in all circumstances under customary international humanitarian law
and is a war crime under the Rome Statute.
137. The Government has in its possession a number of chemical weapons. The dangers
extend beyond the use of the weapons by the Government itself to the control of such
weapons in the event of either fractured command or of any of the affiliated forces gaining
access.
138. It is possible that anti-Government armed groups may access and use chemical
weapons. This includes nerve agents, though there is no compelling evidence that these
groups possess such weapons or their requisite delivery systems.]
139. Allegations have been received concerning the use of chemical weapons by both
parties. The majority concern their use by Government forces. In four attacks – on Khan
Al-Asal, Aleppo, 19 March; Uteibah, Damascus, 19 March; Sheikh Maqsood
neighbourhood, Aleppo, 13 April; and Saraqib, Idlib, 29 April – there are reasonable
grounds to believe that limited quantities of toxic chemicals were used. It has not been
possible, on the evidence available, to determine the precise chemical agents used, their
delivery systems or the perpetrator. Other incidents also remain under investigation.
140. Conclusive findings – particularly in the absence of a large-scale attack – may be
reached only after testing samples taken directly from victims or the site of the alleged
attack. It is, therefore, of utmost importance that the Panel of Experts, led by Professor
Sellström and assembled under the Secretary General's Mechanism for Investigation of
Alleged Use of Chemical and Biological Weapons, is granted full access to Syria.