Vienna: A nuclear reactor being built in Syria during the rule of former President Bashar al Assad was almost complete when it was destroyed by Israeli airstrikes in 2007 and was capable of efficiently producing fissile material that could be used for nuclear weapons, the head of the United Nations nuclear watchdog said on Monday.
International Atomic Energy Agency Director General Rafael Mariano Grossi said the reactor's configuration and technical features made it highly efficient for producing fissile material that could be used directly to make nuclear weapons.
Grossi stressed, however, that the intentions of the Syrian authorities who built the facility could not be determined.
He described the undeclared reactor as a very serious nuclear proliferation concern.
The latest assessment follows an IAEA investigation into Syria's past nuclear activities. The agency has now confirmed its earlier finding that the site in Deir al Zor in eastern Syria was a nuclear reactor under construction.
The reactor was destroyed by Israel in September 2007 before it became operational.
The IAEA said fuel for the reactor had been manufactured in Syria. It also identified a fuel fabrication plant and another location where nuclear fuel, uranium scrap and waste were stored.
The former Syrian authorities should have declared the reactor, the related facilities and the nuclear material to the IAEA under the country's safeguards agreement.
The investigation has advanced significantly since Bashar al Assad was removed from power in December 2024. Syria's new authorities have provided access to sites and information that had previously been unavailable to international nuclear inspectors.
Grossi said the information and access provided by Syria had allowed the agency to clarify and resolve outstanding safeguards issues related to the country's past nuclear activities.
The new Syrian authorities notified the IAEA on July 17 about a previously undeclared location containing nuclear material. They invited the agency to inspect the site and verify the material.
IAEA inspectors later verified about 73 metric tonnes of natural uranium metal at the location. About 55 metric tonnes was in the form of fuel rods.
The material is now subject to IAEA containment and surveillance measures.
Natural uranium metal is not directly usable in a nuclear weapon. The material can, however, be further processed for other nuclear purposes.
The IAEA has installed monitoring equipment at the location to help keep track of the material.
Grossi said the Syrian government would decide whether the uranium remains in Syria or is moved elsewhere. The agency's priority is to ensure that the material remains accounted for and under international safeguards.
IAEA inspectors also visited the Deir al Zor site in August while excavation work was taking place. The agency said features of the site, including cooling infrastructure, were consistent with those of a nuclear reactor.
The reactor site became publicly known after Israel destroyed the facility in 2007. Syria later levelled the site and did not fully answer the IAEA's questions about it.
In 2011, the IAEA Board of Governors found Syria in noncompliance with its safeguards obligations over its failure to declare the reactor and provide required information about its nuclear activities.
The site had previously been linked to suspected North Korean assistance. The IAEA said in 2011 that information available to it indicated that the reactor was being built with North Korean assistance.
Grossi said on Monday that he had not been tasked with carrying out further investigation into alleged North Korean connections. The future of the Syria nuclear file will be considered by the IAEA Board of Governors.
The latest findings do not establish that Syria produced a nuclear weapon or that the reactor ever became operational.
Instead, they confirm that the former Syrian authorities were constructing an undeclared nuclear reactor whose design was highly efficient for producing fissile material that could have been used in nuclear weapons.
Syria's current authorities have said they are committed to cooperation with the IAEA and to keeping nuclear material under international safeguards.
The Syrian Atomic Energy Commission has also said the country intends to expand cooperation with the agency on peaceful uses of nuclear science and technology.
Grossi welcomed Syria's transparency and cooperation, saying that the access and information provided by the new authorities had helped the agency resolve outstanding safeguards questions linked to Syria's past nuclear activities.