President Barack Obama has repeated that the United States is considering all options regarding Iran, and will work with U.S. allies, including Israel, to prevent Iran from acquiring a nuclear weapon.Speaking in Washington on December 8, Obama declined to say what options his administration is considering. But he said Iran's suspected pursuit of nuclear weapons is contrary to the national security interests of the United States and its allies, including Israel, which is widely suspected of having its own nuclear arms."If they [Iran] are pursuing nuclear weapons, then I have said very clearly: That is contrary to the national security interests of the United States, it is contrary to the national security interests of our allies, including Israel, and we are going to work with the world community to prevent that."Obama rejected allegations from opposition Republican Party politicians that his administration hasn't done enough to slow down Iran's nuclear program, saying his administration has systematically imposed what he called "the toughest sanctions on Iran ever."Last month, a United Nations report suggested that Iran had done research toward development of a nuclear weapon. Iran says it is not trying to make an atomic bomb, and that its nuclear program is for peaceful energy generation only.Obama's remarks came the same day that Iranian officialsshowing what appears to be an unmanned U.S. surveillance drone that they claim to have downed over their airspace using high-tech tactics.compiled from agency reports