North Korea claims major nuclear weapons breakthrough with ‘miniaturised’ warheads that can be delivered by missile

North Korea claims it has made a major breakthrough in its nuclear weapons programme, making warheads small enough to fit on missiles.

In a statement issued by its National Defence Commission via the official KCNA news agency, a spokesman said that Kim Jong-un’s secretive state was willing to use the technology to “defend the North” and warned the US not to challenge its military development.