IAEA deepens Syria nuclear probe over uranium traces

Syria's initial explanation of uranium traces U.N. inspectors found at a Damascus atom research reactor is unconvincing and they will take more samples in a deepening probe, the International Atomic Energy Agency said.

In a report obtained by Reuters on Monday, the IAEA said Syria was also still blocking follow-up access to a desert site of what U.S. intelligence reports said was a nascent, North Korean-designed nuclear reactor geared to yield atomic bomb fuel, before Israel bombed it in 2007.

The Vienna-based IAEA, which has been checking whether there could be a link between the Damascus and Dair Alzour sites, said in June particles of processed uranium had showed up in samples at the Damascus research reactor.

Some analysts have said the findings raise the question of whether Syria used some natural uranium intended for the alleged reactor at Dair Alzour for tests applicable to learning how to separate out bomb-grade plutonium from spent nuclear fuel.

Syria, an ally of Iran which is under IAEA investigation over nuclear proliferation suspicions, has denied ever having an atom bomb program and has said the intelligence is fabricated.

Syria told the agency earlier this month that the traces at the Damascus site could have come from domestically-produced uranium concentrate known as "yellow cake", or from imports of commercial uranyl nitrate which it had not declared to the IAEA, according to Monday's report.

The report pointed out that the uranium samples did not fit Syria's earlier explanation for the particles -- that they came from reference materials or from a transport container. It said the type could also not be traced to Syria's declared inventory.

IAEA inspectors will visit the Damascus site on Tuesday to check Syria's latest explanation for the traces and the agency has asked for more information on Syria's yellow cake production and any other materials that could contain uranium particles.

The report said Syria was still refusing IAEA requests for return visits to the bombed Dair Alzour site and had not let the agency visit three military sites, whose appearance was altered by landscaping after the IAEA first asked to check them.

"Essentially, no progress has been made since the last report to clarify any of the outstanding issues," it said.