International Atomic Energy Agency experts have found unexplained plutonium and highly enriched uranium traces in a nuclear waste facility in Iran and have asked Teheran for details, an IAEA report said Tuesday. The report, prepared for next week's meeting of the 35-nation IAEA, also faulted Teheran for not cooperating with the agency's attempts to investigate suspicious aspects of Iran's nuclear program that have led to fears it might be interested in developing nuclear arms. And it said it could not confirm Iranian claims that its nuclear activities were exclusively nonmilitary unless Teheran increased its openness. "The agency will remain unable to make further progress in its efforts to verify the absence of undeclared nuclear material and activities in Iran," without additional cooperation from Teheran, said the report, by IAEA chief Mohamed ElBaradei. Such cooperation is a "prerequisite for the agency to be able to confirm the peaceful nature of Iran's nuclear program," it added.