North Korea and the U.S. fought on opposite sides of a three-year war on the Korean Peninsula before signing a truce in 1953. The Korean Peninsula remains divided by a heavily fortified border, and the U.S. stations 28,000 troops in South Korea to protect the ally.
However, even before late leader Kim Jong Il's death a year ago, North Korea indicated interest in repairing relations with Washington.
Last year, a group of North Koreans even visited Google headquarters in Mountain View, California.
___Associated Press technology writer Youkyung Lee contributed to this report. Follow AP's Korea bureau chief at www.twitter.com/newsjean and AP Seoul's technology writer at www.twitter.com/ykleeAP.