NKorea Nuclear Envoy to Visit US on Heels of Deal In another sign of warming relations between two wartime foes, a senior North Korean nuclear negotiator will attend a security conference in the United States, a person with knowledge of the negotiations between Washington and Pyongyang told The Associated Press on Thursday. Word of Ri Yong Ho's visit to the forum at Syracuse University, where he may also meet on the sidelines with U.S. officials, comes on the heels of a breakthrough agreement that will provide much-needed U.S. food aid to North Korea in exchange for a rollback of its nuclear programs. The agreement announced Wednesday sets in motion a plan laid out by North Korean leader Kim Jong Il before his death in December: to improve relations with the U.S. and to get back to six-nation disarmament-for-aid negotiations. Significant challenges remain, however, in achieving the long-term goal of the U.S. and other nations: to persuade Pyongyang to end its nuclear ambitions altogether. First, diplomats need to iron out the tricky logistics of distributing, and monitoring, the 240,000 metric tons of U.S. food aid earmarked for hungry North Korean children. They also need to work out a timeline for the return of U.N. nuclear inspectors tasked with verifying whether Pyongyang sticks to its promises. In this Monday Feb. 27, 2012 file photo, North Korea's First Vice Foreign Minister Kim Kye Gwan, left, is greeted by Ri Yong Ho, a vice minister of North Korea's Ministry of Foreign Affairs, at Pyongyang airport in North Korea, Monday, Feb. 27, 2012. Ri, the North Korean vice foreign minister in charge of nuclear negotiations, is heading to New York next week on the heels of a breakthrough nuclear agreement with the U.S., two people with knowledge of negotiations between Washington and Pyongyang told The Associated Press on Thursday. (AP Photo) Close And while the deal paves the way for unprecedented exchanges with the U.S., North Korea still must confront the complicated matter of improving relations with rival South Korea, still smarting from two deadly incidents in 2010 that Seoul blames on Pyongyang. Still, there was cautious hope that North Korea's relations with the U.S. and its allies have turned a corner after years of tensions. The agreement calls on Pyongang to suspend uranium enrichment and place a moratorium on nuclear and long-range missile tests. In a possible sign of things to come, Ri, North Korea's vice foreign minister and envoy to nuclear disarmament negotiations, has been cleared to travel to the U.S. to attend the forum at Syracuse University, according to the person with knowledge of the arrangement. A second person with information about Ri's itinerary also said the envoy would be attending the Syracuse forum. Both spoke on condition of anonymity because Ri's travel plans have not been formally announced. The U.S. and North Korea do not have formal diplomatic relations but the measures laid out in the deal announced Wednesday include facilitating "people-to-people" exchanges. The deal is a sign that the foreign policy laid out in the final years of Kim Jong Il's rule - with improved relations with the U.S. as a key goal - will be carried out by his young son. Shortly before Kim Jong Il's death was announced, the AP reported that a deal similar to the one announced this week was imminent. A return to negotiations before the end of the semiofficial 100-day mourning period suggests stability and continuity during the closely watched transition of leadership in North Korea. In Pyongyang, a spokesman for North Korea's Foreign Ministry told the state-run Korean Central News Agency that the steps are confidence-building measures designed to improve relations between North Korea and the U.S. The U.S. and North Korea fought on opposite sides of the Korean War and signed an armistice to end the fighting in 1953. They have never signed a peace treaty, and the U.S. has some 28,000 troops protecting ally South Korea.