OPCW Says More Than 100 Chemical Sites Remain in Syria

May 2025
By Mina Rozei

More than 100 chemical weapons sites associated with ousted Syrian President Bashar al-Assad’s regime are believed to remain in Syria, a far higher number than previously estimated, according to the Organisation for the Prohibition of Chemical Weapons (OPCW).

The new estimate was first reported by The New York Times April 5 and confirmed for Arms Control Today by OPCW Director-General Fernando Arias in an email exchange April 18.

Arias said that the estimated number of sites is based on a combination of the Syrian government’s own declaration when it joined the OPCW in 2013; the work of the OPCW Declaration Assessment Team, which is composed of investigation experts, information from OPCW member states; and information from the interim Syrian government that took office when Assad fled Syria in December.

“It is the correlation and analysis of all this information that allowed the Secretariat to consider that more than 100 locations in Syria need to be visited,” he told Arms Control Today.

Arias said that the “inaccurate and incomplete” nature of Syria’s initial declaration, which detailed more than 40 years of Syrian chemical weapons development and stockpiling, has been a major stumbling block over the last 10 years as the OPCW attempted to address the remaining stockpile.

The current transitional government in Damascus appears to be taking a more open and transparent approach to the issue, even declaring its disapproval of the Assad regime’s use of chemical weapons. (See ACT, April 2025.)

Syrian Foreign Minister Asaad al-Shaibani has been working closely with the OPCW at the invitation of Arias, who invited the minister to appoint experts to discuss the Syrian chemical weapons program in full, including parts that had not been declared by the Assad government. “I informed the minister that the [OPCW Technical] Secretariat was ready to deploy and shared a roadmap we had developed to work together to establish an inventory of all that needs to be declared and verified,” Arias said.

Arias met Syria’s transitional president, Ahmed al-Sharaa, and Shaibani in Damascus and characterized the meetings as an opportunity to “exchange points of view and information in detail in a sincere and open manner and in a constructive atmosphere.... During these visits we have found goodwill and active cooperation on the Syrian side.”

He emphasized that with the cooperation of the current transitional Syrian government, there is a renewed push to finally eliminate the Syrian chemical weapons program and close the file. The OPCW and the Syrian government are working in tandem to hold accountable those responsible for past chemical attacks. Arias said that the OPCW is sharing its expertise to support Syria’s capacity building and knowledge in case of future attacks, perhaps alluding to the insecurity of the remaining stockpile.

Arias sees this renewed cooperation as a turning point in the work of the OPCW and stressed that Sharaa “mentioned that he wanted Syria to become a positive example for the region and the world in dealing with chemical weapons and their tragic and lasting footprint in this country.”

“We know that we will have to overcome many obstacles, but we also know that we can and will count on the support of the new authorities,” he said.