The UN nuclear watchdog admitted today that it had wrongly accused Iran of withholding information about imports of potentially weapons-related machinery.
Iran is likely to seize on the admission to call into doubt the investigations into what Tehran says is a peaceful nuclear power programme but what Washington says is a front for developing atomic weapons.
The International Atomic Energy Agency (IAEA) said in a June 1st report that Iran did not declare it had imported parts for advanced P-2 centrifuges until April. But the Iranians have produced a tape recording of a conversation proving they informed the agency verbally in January.
"This oral statement was not picked up by the agency inspectors and was therefore not reflected in" the International Atomic Energy Agency's latest report on Iran issued on June 1st," senior IAEA inspector Mr Pierre Goldschmidt said in a statement to the agency's board of governors.
However, IAEA chief Mr Mohamed ElBaradei said that it was a minor error on part of the agency, and one that the Iranians could have helped to correct before it got into the report.
"You have to understand we work with thousands of papers and thousands of sites," Mr ElBaradei said. "Everybody makes mistakes."
The IAEA investigation of Iran began shortly after an exiled Iranian opposition group reported in April 2002 that Tehran was hiding a massive enrichment plant at Natanz and other facilities from the IAEA.