North Korea says it conducted the final ground test of a solid-fuel rocket engine for a long-range ballistic missile in its latest advancement toward having an arsenal that could viably threaten the continental United States.

Technology has allowed North Korea to increase control of its citizens over the last decade with some being executed for distributing foreign TV programs, according to the United Nations.

The plan reflects North Korean leader Kim Jong Un's view that nuclear forces alone have limits as a deterrent, and that Pyongyang is seeking to boost its war-fighting capability by modernising its conventional arsenal,

At the launch of the Corporate Growth Forum held in Seoul on Thursday, Korea Chamber of Commerce and Industry (KCCI) Chairman Chey Tae-won highlighted the need to overhaul regulatory structures that, he said, are stifling business momentum at every stage of expansion.

South Korean foreign ministry officials confirmed to ABC News that 300 detainees were scheduled to fly out of Atlanta on Wednesday, but “because of circumstances on the U.S. side, the plane’s departure from Atlanta will be delayed”.