WASHINGTON - Iran has enough material to build a nuclear bomb, US Chairman of the Joint Chiefs of Staff Michael Mullen said Sunday. "We think they do, quite frankly," Mullen told CNN's "State of the Union" presided by John King, when asked if Iran had enough nuclear material to build the nuke. "And Iran having a nuclear weapon, I've believed for a long time, is a very, very bad outcome for the region and for the world," said the top US Army officer. In a report submitted last month to the UN Security Council, Mohamed El Baradei, Director General of the International Atomic Energy Agency (IAEA) said Iran still refused to fulfil UN's requirement of stopping its uranium enrichment activity. Responding to the IAEA report, Iran has vowed to continue its nuclear work. Iran's uranium enrichment programme is questioned by many parties. Western countries like the United States claim that Iran intends to secretly develop nuclear weapons, while the UN Security Council also requires Iran to suspend its uranium enrichment activity. However, Iran insists that its nuclear plan is only for peaceful purposes.