SEOUL (Reuters) - North Korea represents a threat not just to Asia but to the United States, U.S. President Barack Obama said on Friday, as he and South Korea's President Park Geun-hye warned they would respond firmly to any "provocations".
In March, the North warned it would not rule out a "new form" of nuclear test to boost its nuclear deterrent, after the U.N. Security Council condemned Pyongyang's launch of a mid-range ballistic missile into the sea east of the peninsula.
