Conference of the States Parties Adopts Decisions to Amend Chemical Weapons Convention Annex

27 November 2019

THE HAGUE, Netherlands — 27 November 2019 — The Chemical Weapons Convention (CWC), banning the development, production, use, stockpiling and transfer of chemical weapons, entered into force in 1997. Today, the Twenty-Fourth Session of the Conference of the States Parties to the CWC has adopted two decisions to amend for the first time the Annex on Chemicals to the Convention.

The two decisions adopted reflect proposals that were submitted in the context of an evolving threat from chemical weapons and their recent use, which require the OPCW to continually adjust its ability to respond. Such conditions have led to the need to update the Schedules of the Annex on Chemicals. The first decision was jointly proposed by Canada, the Netherlands, and the United States of America while the second decision was proposed by the Russian Federation. Both decisions call for Technical Changes to Schedule 1 of the Annex on Chemicals to the CWC.

The Director-General of the Organisation for the Prohibition of Chemical Weapons (OPCW), H.E. Mr Fernando Arias, recognised the importance of these amendments: “This is the first time in its history that the Chemical Weapons Convention’s Annex on Chemicals has been updated. This is an important development that demonstrates the adaptability of the Convention to changing threats while enhancing the OPCW’s ability to remain vigilant, agile, and fit for purpose.”

The Annex on Chemicals includes three Schedules that list toxic chemicals and their precursors. For the purpose of implementing the Convention, these Schedules identify chemicals for the application of special verification measures according to the provisions of the Convention’s Verification Annex.

As required under subparagraph 5(f) of Article XV of the CWC, the Director-General will notify all States Parties and the Convention’s Depositary, the United Nations Secretary-General, of the decisions adopted by the Conference. This notification will include the merged text of the proposals, which will be prepared by the Secretariat for inclusion in the Annex on Chemicals. The changes to the Schedule of the Annex on Chemicals will enter into force for all States Parties 180 days from the date of the notification sent by the OPCW Director-General.


The Twenty-Fourth Session of the Conference of the States Parties (CSP-24) will be held from 25-29 November 2019 in The Hague. The CSP is the principal organ of the OPCW and consists of representatives from each of the Organisation’s Member States. The Conference meets annually and oversees the implementation of the Chemical Weapons Convention, promotes the treaty’s objectives and reviews compliance with the treaty.

As the implementing body for the Chemical Weapons Convention, the OPCW, with its 193 Member States, oversees the global endeavour to permanently eliminate chemical weapons. Since the Convention’s entry into force in 1997, it is the most successful disarmament treaty eliminating an entire class of weapons of mass destruction.

Over 97% of all chemical weapon stockpiles declared by possessor States have been destroyed under OPCW verification. For its extensive efforts in eliminating chemical weapons, the OPCW received the 2013 Nobel Peace Prize.

More Information