Iran could complete the manufacture of an atomic bomb within a year, and is just waiting for supreme leader Ayatollah Ali Khamenei to give the go-ahead, according to intelligence sources quoted in a report by The Times on Monday. The sources were further quoted by the British newspaper as saying that the Islamic republic had put a stop to its nuclear arms research program back in 2003 as it had already developed the means to detonate a nuclear warhead which could be launched on the Shahab-3 long-range missile. Once Khamenei gives the word, the sources said, six months would be needed to "enrich low-enriched uranium to highly-enriched uranium at the Natanz plant," and a further six months to put together the warhead itself. The Times report stated that Iranian scientists had been working on a "multipoint initiation system" using an agency called 'Amad.' The system, according to the article, uses a "series of explosive grooves on a metal hemisphere covering the uranium, which links explosives-filled holes opening onto a layer of high explosives enveloping the uranium." The sources told The Times that they were not sure whether or not Khamenei had made the decision to go ahead with the bomb. The report also quoted an Israeli official as evaluating that Teheran had spent billions of dollars on enriching uranium and developing a nuclear weapon over the last 30 years. He was quoted as saying that the country had enriched enough low-grade uranium to make one bomb.