The worry stems from the Assad regime’s attempt to build a nuclear reactor in the eastern city of at Al-Kibar in the mid-2000s. With assistance from North Korea, Damascus is believed to have nearly completed the facility prior to its destruction in an alleged Israeli airstrike in 2007.

Few details are known about the nature of the reactor, although experts believe the plant would have required approximately 50 tons of natural uranium fuel to become operational.

An IAEA inspection team that visited the Al-Kibar site in May 2008 found only traces of uranium, fueling speculation that a large stockpile of uranium had been moved.

David Albright, the head of the US-based Institute for Science and International Security think-tank, and a leading expert on the Iran’s nuclear program, was quoted by the Financial Times as saying that “There are real worries about what has happened to the uranium that Syria was planning to put into the Al-Kibar reactor shortly before the reactor was destroyed.