The U.N. political affairs chief on Saturday ended a rare visit to North Korea after holding talks with senior diplomats, but apparently with a lack of major progress in stopping the country's accelerating nuclear weapons and missile programs.Shortly after Jeffrey Feltman, undersecretary general for political affairs, departed from Pyongyang, North Korea's official news agency put out a report summarizing his visit saying the country told him the United States is totally responsible for the current tense situation on the Korean Peninsula.Feltman later arrived in Beijing but did not make any…READ FULL ARTICLE