evidence: North Korea’s army said it will take the "substantial military step" of completely cutting off its territory from South Korea on Wednesday, after months of fortifying its heavily armed border. [...] "If North Korea were to establish a new territorial clause through a constitutional amendment and sever its relationship with the South, the internal and external repercussions would be so great," Hong told CNN, suggesting Pyongyang is taking small steps in that direction. [...] North and South Korea have been separated since the Korean War ended in 1953 with an armistice agreement. The two sides are still technically at war, but both governments had long sought the goal of one day reunifying.