A top official from the UN's nuclear watchdog arrived in Teheran Thursday for talks over the country's disputed nuclear program, Iranian state TV reported. According to the report, the deputy director general of the International Atomic Energy Agency, Olli Heinonen, will be in Iran for two days. It was unclear whether he planned discuss Iran's response to an incentives package offered by six world powers, in exchange for a promise from Teheran to curb uranium enrichment. The US called the response unacceptable, and the group agreed to pursue another round of sanctions against Iran. The Vienna-based IAEA has been monitoring Iran's existing nuclear program, and investigating whether Iran is trying to develop nuclear weapons. Teheran claims its uranium enrichment is for peaceful purposes only, to generate electricity.