WASHINGTON (AP) - Defence Secretary Chuck Hagel says neither Iran nor North Korea is capable of attacking the United States with a missile armed with a nuclear warhead.

North Korea has acknowledged that it is working on such a capability and has threatened to use it. US missile defenses are positioned in the Pacific in anticipation of a possible North Korean missile launch in coming days.

Mr Hagel was responding to a question at a House Armed Services Committee hearing on Thursday. He said that while he does not believe North Korea or Iran has a long-range missile that can hit the US with a weapon of mass destruction, he did not rule out that either country could eventually acquire such a capability.