Communication dated 18 June 2009 received from the Permanent Mission of the Islamic Republic of Iran to the Agency Concerning Statements made by the Islamic Republic of Iran in the Board of Governors
Iran has installed several cascades of more powerful centrifuge models in production lines, where they have steadily increased both the size and enrichment level of Iran's uranium stockpile. This progress increases the risk of secret sites – permitting them to be smaller and easier to hide. Iran has used such sites to carry out illicit activity in the past and they continue to pose the greatest nuclear weapon risk.