Iran downplayed on Saturday as a "technical" issue a report by the UN atomic watchdog revealing that uranium traces of a higher grade than any found before had been detected.
Higher-than-expected traces of enriched uranium "are a normal technical issue that is being investigated by (IAEA) experts," Iran's envoy to the International Atomic Energy Agency Ali Asghar Soltanieh was quoted as telling the official IRNA news agency.
The agency report said that the traces found at the Fordo site, inside a mountain bunker near Qom, were of uranium enriched to purities of 27 percent. Previously, the highest level recorded by the agency in Iran was 20 percent.
The West fears that Iran could be covertly aiming to enrich uranium towards the 90 percent needed to develop atomic bombs, a claim Tehran vehemently denies.
"Addressing technical and trivial issues, which also occur in the nuclear facilities of other nations, show media reports are seeking political goals," Soltaneih said.
"Highlighting and politicising a technical issue is a sign of efforts to damage the atmosphere of constructive cooperation between Iran and the agency," added the envoy, whose initial reaction did not refer to the discovery of higher-grade uranium traces.
"The report once again proves to the international community that all Iranian nuclear activities are successfully underway and are uninterrupted, and that there is no diversion in Iran's nuclear material towards military objectives," he had said late on Friday.
The report, he said, "is more proof of the peaceful nature of Iran's nuclear activities and of our country's success in the field of nuclear technology, in particular enrichment, and its full cooperation with the agency."
Analysts cautioned that the 27% find could just be a processing glitch and not necessarily a sign of a deliberate effort to enrich above 20%.
In the IAEA report, which was seen by AFP, Iran also explained that enrichment above 20% "may happen for technical reasons beyond the operator's control."
The report said the IAEA was "assessing Iran's explanation and has requested further details." Early this month it took samples from the site that were being analysed.