Saturday, September 3 2005 10:28 Hrs (IST) - World Time -

Vienna: Iran has produced tons of the gas used in uranium enrichment since last month, when it resumed the process that can be used to make nuclear weapons, a UN report said yesterday (Sept 2, 2005).

In unusually strong language, the report also said questions remain about key aspects of 18 years of clandestine nuclear activity on the part of Iran despite more than two years of investigations by the International Atomic Energy Agency.

"The agency is not yet in a position to clarify some important outstanding issues after 2 1/2 years of intensive inspections and investigation," said the restricted document seen by the sources. "Iran's full transparency is indispensable and overdue."

Among the unanswered questions, according to the report, were gaps in the documented development of Iran's centrifuge programme used in uranium enrichment and in what was received, and when, from the black market network headed by Pakistani scientist A Q Khan.

Overall, the report confirmed earlier recent revelations that most of the traces of weapons-grade uranium were imported to Iran on equipment from Pakistan that it bought on the black market - even though it said that, "it is still not possible at this time to establish a definite conclusion," particularly about the origins of other traces enriched to less than weapons grade.

That finding hurts US arguments that the traces were likely the result of enrichment done in Iran, as part of attempts to make weapons-grade uranium.