NORTH KOREA could be able to launch a nuclear attack on the United States in less than six months despite sanctions starting to have a large effect on the population, East Asia expert Gordon Chang warned. North Korea's leader Kim Jong-un warned he was ready to press the "nuclear button" on his desk to hit the United States, possibly kickstarting World War 3.

But Mr Chang said the international community has between three to six months before North Korea reaches nuclear capability to defuse tensions. He said: "Kim Jong-un actually doesn’t have a button he can push right now. Maybe three months, six months from now, he can pick up the phone and launch a nuke at the United States. "The one thing Kim can do is launch an electromagnetic pulse device: he doesn’t need heat shielding, he doesn’t need guidance. He could do a lot of damage to the United States."