Iran has further increased its stockpile of uranium enriched to near weapons-grade levels, according to a confidential May 27 report by the International Atomic Energy Agency (IAEA). Iran's stockpile of uranium enriched to 60 percent purity is now 142.1 kilograms -- an increase of 20.6 kilograms since the watchdog's last report in February. The IAEA also said that the deaths of Iran's president and foreign minister in a helicopter crash on May 19 have forced a pause in the UN nuclear watchdog's talks with Tehran over improving cooperation.