US President Barack Obama has told an Israeli television channel it would take Iran "over a year or so" to develop a nuclear weapon. In an interview with Channel 2 he said he did not want to "cut it too close" and declined to rule out the possibility of military action. Iran's nuclear programme is expected to be high on the agenda when Obama visits Israel later this month. Tehran insists it is refining uranium only for peaceful energy purposes. But Israel has repeatedly threatened a military strike if Iran appears to be on the verge of obtaining a bomb. Washington is pushing for more time to allow diplomacy and economic sanctions to run their course.