SEOUL, March 22 - North Korea on Friday pulled out of a liaison office with South Korea just north of their armed border, in a setback for South Korean President Moon Jae-in's effort to end hostility and in the wake of a failed summit between the North and the United States. North Korea conveyed the decision during a weekly meeting with the South on Friday morning saying it was on 'instructions from a higher level,' South Korea's Vice Unification Minister Chun Hae-sung told a news briefing.