Syria and chemical weapons – documents

International law

The Geneva Protocol (1925)
"For the prohibition of the use in war of asphyxiating, poisonous or other gases, and of bacteriological methods of warfare."

Chemical Weapons Convention (effective from 1997)
"On the prohibition of the development, production, stockpiling and use of chemical weapons and on their destruction."

Note by OPCW Technical Secretariat (2021)
On allegations by the Syrian government regarding chemical weapons in rebel hands


UN Security Council resolutions

Security Council Resolution 2118
27 September 2013
Demands Syria's compliance with the OPCW in "the expeditious destruction" of its chemical weapons programme. Adopted unanimously.

Security Council Resolution 2209
6 March 2015
Expresses "deep concern" that toxic chemicals, including chlorine, have been used as a weapon in Syria. Calls on all parties in Syria to extend their full cooperation to the OPCW Fact-Finding Mission

Security Council Resolution 2235
7 August 2015
Asks the UN Secretary-General to make plans for establishing a OPCW-UN Joint Investigative Mechanism to "identify to the greatest extent feasible individuals, entities, groups, or governments who were perpetrators, organisers, sponsors or otherwise involved in the use of chemicals as weapons ..."

Security Council Resolution 2314
31 October 2016
Extends the mandate of UN-OPCW Joint Investigative Mechanism to 18 November 2016.

Security Council Resolution 2319
17 November 2016
Renews mandate of the UN-OPCW Joint Investigative Mechanism for a further year.


Draft Security Council resolutions (not adopted)

Note: In order to be adopted, draft resolutions on non-procedural matters need affirmative votes from nine of the 15 council members, including those of all five permanent members.

S/2018/175
10 April 2018
Russian draft resolution on proposal to establish a United Nations Independent Mechanism of Investigation. Failed to gain the necessary nine votes.

S/2018/321
​10 April 2018
US draft resolution on proposal to establish a United Nations Independent Mechanism of Investigation. Vetoed by Russia.

S/2018/322
​10 April 2018
Russian draft resolution on the OPCW Douma investigation. Failed to gain the necessary nine votes.

S/2017/970
17 November 2017
Japanese draft resolution to extend mandate of the Joint Investigative Mechanism by 30 days. Vetoed by Russia.

S/2017/962
16 November 2017
US draft resolution to renew mandate of the Joint Investigative Mechanism for a further 12 months. Vetoed by Russia.

S/2017/968
​16 November 2017
Russian draft resolution to renew mandate of the Joint Investigative Mechanism for a further 12 months. It was put to a vote by Bolivia but failed to gain the necessary nine votes.

S/2017/884
24 October 2017
Draft resolution to renew mandate of the Joint Investigative Mechanism for a further year. Vetoed by Russia.

S/2017/315
12 April 2017
Draft resolution calling on Syria to cooperate with investigations. Vetoed by Russia.

S/2017/172
28 February 2017
Draft resolution calling on member states to prevent supply of certain chemicals, plus helicopters and spare parts. Vetoed by Russia and China.
See also: UN press release giving an account of the debate, and a letter from France, UK and US dated 24 February 2017.


UN mission on Ghouta

S/2013/553
13 September 2013
Report of the United Nations Mission to Investigate Allegations of the Use of Chemical Weapons in the Syrian Arab Republic on the alleged use of chemical weapons in the Ghouta area of Damascus on 21 August 2013.


OPCW Fact-Finding Mission reports

S/2020/2022
31 January 2022
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incident of the Alleged Use of Chemicals as a Weapon in Kafr Zeita, Syrian Arab Republic, on 1 October 2016

S/2017/2022
24 January 2022
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incidents of the Alleged Use of Chemicals as a Weapon in Marea, Syrian Arab Republic, on 1 and 3 September 2015

S/1902/2020
1 October 2020
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incident in Aleppo, Syrian Arab Republic on 24 November 2018

S/1901/2020
1 October 2020
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incident of Alleged Use of Chemicals as a Weapon in Saraqib, Syrian Arab Republic, on 1 August 2016

S/1731/2019
1 March 2019
Report of the Fact-Finding Mission Regarding the Incident of Alleged Use of Toxic Chemicals as a Weapon in Douma, Syrian Arab Republic, on 7 April 2018

S/1645/2018
6 July 2018
Interim Report on the Progress of the Fact-Finding Mission Regarding an Incident of Alleged Use of Toxic Chemicals as a Weapon in Douma, Syrian Arab Republic, on 7 April 2018. See also corrigendum: S/1645/2018/Corr.1

S/1642/2018
2 July 2018
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incidents in Al-Hamadaniyah on 30 October 2016 and in Karm Al-Tarrab on 13 November 2016

S/1636/2018
13 June 2018
Report of the OPCW Fact-Finding Mission in Syria Regarding Alleged Incidents in Ltamenah, the Syrian Arab Republic on 24 and 25 March 2017

S/1626/2018
15 May 2018
Report of the OPCW Fact-Finding Mission in Syria Regarding an Alleged Incident in Saraqib, Syrian Arab Republic on 4 February 2018. See also corrigendum: S/1626/2018/Corr.1

S/1548/2017
2 November 2017
Report of the OPCW Fact-Finding Mission in Syria Regarding An Alleged Incident in Ltamenah, the Syrian Arab Republic, 30 March 2017

S/1510/2017
29 June 2017
Report of the OPCW Fact-Finding Mission in Syria regarding an alleged incident in Khan Shaykhun, Syrian Arab Republic April 2017

S/1491/2017
1 May 2017
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incident of 16 September 2016 as Reported in the Note Verbale of the Syrian Arab Republic Number 113 dated 29 November 2016

S/1445/2016
27 December 2016
Summary Update of the Activities Carried Out by the OPCW Fact-Finding Mission in Syria in 2016

S/1444/2016
21 December 2016
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incident of 2 August 2016 as Reported in the Note Verbale of the Syrian Arab Republic Number 69 dated 16 August 2016

S/1318/2015/Rev.1/Add.1
29 February 2016
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incidents Described in Communications from the Deputy Minister for Foreign Affairs and Expatriates and Head of the National Authority of Syria - Addendum

S/1318/2015/Rev.1
17 December 2015
Report of the OPCW Fact-Finding Mission in Syria Regarding the Incidents Described in Communications from the Deputy Minister for Foreign Affairs and Expatriates and Head of the National Authority of Syria. See also S/1318/2015.

S/1319/2015
29 October 2015
Report of the OPCW Fact-Finding Mission in Syria Regarding Alleged Incidents in the Idlib Governorate of the Syrian Arab Republic Between 16 March and 20 May 2015

S/1320/2015
29 October 2015
Report of the OPCW Fact-Finding Mission in Syria Regarding Alleged Incidents in Marea, Syrian Arab Republic, August 2015

S/1230/2014
18 December 2014
Third Report of the OPCW Fact-Finding Mission in Syria

S/1212/2014
10 September 2014
Second Report of the OPCW Fact-Finding Mission in Syria Key Findings. See also corrigendum: S/1212/2014/Corr.1

S/1191/2014
16 June 2014
Summary Report of the Work of the OPCW Fact-Finding Mission in Syria Covering the Period from 3 to 31 May 2014. See also corrigendum: S/1191/2014/Corr.1


Elimination of Syria's chemical weapons programme

Framework for Elimination of Syrian Chemical Weapons
14 September 2013
Joint national paper by Russia and the United States

Monthly progress reports from the OPCW to the UN Security Council are listed here.


Joint Investigative Mechanism

1st report
12 February 2016

2nd report
10 June 2016

3rd report
24 August 2016 (also revised version)

Syrian response to 3rd report
20 October 2016

4th report
21 October 2016

5th report
13 February 2017

6th report
28 June 2017

Remarks by Edmond Mulet
6 July 2017
Transcript of news conference given by the head of the JIM

Russian critique of the Khan Shaykhun investigation
10 October 2017

7th report
26 October 2017


International, Impartial and Independent Mechanism

UN General Assembly resolution (A/RES/71/248)
21 December 2016
Resolution establishing the International, Impartial and Independent Mechanism "to assist in the investigation and prosecution of those responsible for the most serious crimes under international law committed in the Syrian Arab Republic since March 2011". Resolution drafted by Liechtenstein and passed with 105 votes in favour, 15 against and 52 abstentions.

Terms of reference of the International, Impartial and Independent Mechanism

A/72/764
28 February 2018
First report of the International, Impartial and Independent Mechanism

A/73/295
3 August 2018
Second report of the International, Impartial and Independent Mechanism

A/73/741
13 February 2019
Third report of the International, Impartial and Independent Mechanism


Conference of the States Parties

C-25/DEC.9
21 April 2021
Addressing the possession and use of chemical weapons by the Syrian Arab Republic

EC-M-60/1
29 May 2018
Request for a special session of the Conference of the States Parties to discuss "upholding the global ban against chemical weapons use". Submitted by the United Kingdom on behalf of Australia, Bulgaria, Canada, France, Germany, Japan, New Zealand, Poland, Romania, the United Kingdom and the United States.

Statement by Iran
4 June 2018
Opposing a special session of the Conference of the States Parties

Russian draft proposal
21 June 2018
"Enhancing the capacity of the OPCW to combat the threat of use of chemical weapons"

C-SS-4/DG.4
Opening Statement by the Director–General to the Conference of the States Parties at its Fourth Special Session
26 June 2018

C-SS-4/DEC.3
Decision of the Conference of the States Parties: "Addressing the Threat from Chemical Weapons Use"
27 June 2018

C-SS-4/3
Report of the Fourth Special Session of the Conference of the States Parties
27 June 2018

Statements by member countries at the Conference of the States Parties (compilation of links to individual statements)

C-SS-4/INF.1/Rev.1
List of Participants of the Fourth Special Session of the Conference of the States Parties
27 June 2018

C-SS-4/DEC.1
Attendance and Participation by Non-Governmental Organisations at the Conference of the States Parties
26 June 2018

Statement by Paul Walker of Green Cross International
26 June 2018

Statement by Professor Ulf Schmidt of Fritz-Haber-Institute
26 June 2018


Investigation and Identification Team (IIT)

S/1943/2021
12 April 2021
Second Report by the Investigation and Identification Team, on events in Saraqib, 4 February 2018

S/1867/2020 
8 April 2020 
First Report by the Investigation and Identification Team, on events in Ltamenah, 24, 25, and 30 March 2017

Director-General’s statement
8 April 2020

IIT Coordinator’s remarks
8 April 2020

C-SS-4/DEC.3
Decision of the Conference of the States Parties: "Addressing the Threat from Chemical Weapons Use"
27 June 2018

EC‑89/DG.2
27 July 2018
Initial Implementation of Decision C-SS-4/DEC.3 on Addressing the Threat from Chemical Weapons Use

EC‑89/DG.29
4 October 2018
Progress in the Implementation of Decision C-SS-4/DEC.3 on Addressing the Threat from Chemical Weapons Use

C‑23/DG.16 RC‑4/DG.4
15 November 2018
Note by the Director-General: Report on Proposals and Options Pursuant to Paragraph 21 of Decision C-SS-4/DEC.3, dated 27 June 2018, on Addressing the Threat from Chemical Weapons Use

EC‑90/DG.14
7 March 2019
Progress in the Implementation of Decision C-SS-4/DEC.3 on Addressing the Threat from Chemical Weapons Use

EC‑91/S/3 
28 June 2019
Work of the Investigation and Identification Team Established by Decision C-SS-4/DEC.3 (Dated 27 June 2018)

S/1867/2020
8 April 2020
First report of the IIT, on incidents in Ltamenah, 24, 25, and 30 March 2017. Attributes two chlorine attacks and one sarin attack to Syrian government forces.

S/1943/2021
12 April 2021
Second report of the IIT, on incident in Saraqib, 4 February 2018. Attributes chlorine attack to Syrian government forces.

S/2125/2023
27 January 2023
Third report of the IIT, on incident in Douma, 7 April 2018. Attributes chlorine attack to Syrian government forces.


The Douma controversy

Documents relating to the alleged use of toxic chemicals as a weapon in Douma, Syria, on 7 April 2018.

United States Government Assessment of the Assad Regime’s Chemical Weapons Use
13 April 2018

French national assessment
14 April 2018
"Chemical attack of 7 April 2018 (Douma, Eastern Ghouta, Syria); Syria’s clandestine chemical weapons programme"

Minutes of meeting with toxicologists
Held on 6 June 2018

Draft interim report on Douma (unredacted)
June 2018
Published by WikiLeaks 14 December 2019

Draft interim report on Douma (after redaction)
June 2018
Published by WikiLeaks 14 December 2019

Internal OPCW email
22 June 2018
Published by WikiLeaks 23 November 2019

Exchange of emails with Sami Barrek, inspection team leader
4-5 July 2018
Published by WikiLeaks 14 December 2019

S/1645/2018
6 July 2018
Interim report by the OPCW Fact-Finding Mission

Emails relating to membership of the Fact-Finding Mission
30 July 2018

Emails relating to meeting with toxicologists
20-30 August 2018

Leaked "Engineering Assessment"
27 February 2019
Internal document authored by OPCW employee Ian Henderson which disputed the Fact-Finding Mission's report on Douma
Leaked online 13 May 2019

Emails relating to Henderson's "Engineering Assessment"
27-28 February 2019

S/1731/2019
1 March 2019
Final report by the OPCW Fact-Finding Mission

Memo from Ian Henderson to Fernando Arias, OPCW Director-General
14 March 2019
Published by WikiLeaks 14 December 2019

EC‑90/NAT.41
26 April 2019
Russian response to the Fact-Finding Mission's report

Letter from Brendan Whelan to OPCW Director-General
25 April 2019
Published by The Grayzone

Email to Veronika Stromšíková, Director of the Office of Strategy and Policy
20 May 2019
Published by WikiLeaks 14 December 2019

S/1755/2019
21 May 2019
OPCW replies to Russian and Syrian critiques of its Douma report

Statement by the Courage Foundation panel
23 October 2019

Analytical points by the Courage Foundation panel
23 October 2019

Written statement by Ian Henderson
18 January 2020 (leaked 11 February 2020)

Oral statement by Ian Henderson
20 January 2020

Report of the investigation into possible breaches of confidentiality
6 February 2020

Note Verbale from Syrian mission at the OPCW
20 April 2020

S/2125/2023
27 January 2023
IIT report on Douma confirms chlorine attack and blames to Syrian government forces.