US intelligence: Iran 4 years from nuclear weapon

US intelligence agencies estimate that Iran might be able to develop a nuclear weapon within four years, the US intelligence director said in an interview broadcast Friday. National Intelligence Director John Negroponte told British Broadcasting Corp. radio that the time frame in which Iran might develop a weapon was uncertain. "This is a matter of assessment, we don't have a clear-cut knowledge," Negroponte said. "But the estimate we have made is that some time between beginning of the next decade and the middle of the next decade they might be in a position to have a nuclear weapon."