It was many years in the works but South Korea and the United States have finally put pen to paper on their updated nuclear energy cooperation pact.<br />The deal still needs to undergo a lengthy review process by the U.S. Congress, but it's expected to take effect by the end of this year.<br />Hwang Sung-hee reports.<br /><br />Korean Foreign Minister Yun Byung-se and U.S. Energy Secretary Ernest Moniz signed the revised civilian nuclear energy cooperation agreement on Monday in Washington, ending four years of arduous negotiations.<br />While the new deal -- updated from the existing 1974 pact -- still bans Seoul from reprocessing and enrichment, it allows Korea to research a new technology for recycling spent nuclear fuel and to make low-level enriched uranium with U.S. consent.<br />The agreement awaits approval from the U.S. Congress, but both sides said the deal strengthens their alliance.<br /><br />"Together with the mutual defense treaty of 1954 and the Korea-U.S. FTA of 2012, this nuclear agreement will be another key pillar of our alliance."<br /><br /><br />"The U.S.-Korea partnership is an absolute anchor for peace and stability."<br /><br /><br />In Washington, Korea's top diplomat also met with U.S. National Security Adviser Susan Rice to discuss the possible rescheduling of President Park Geun-hye's visit to the country.<br />The Korean leader postponed her trip last week to handle the outbreak of Middle East Respiratory Syndrome, or MERS, in Korea.<br />Yun said Seoul will push for a summit with U.S. President Barack Obama within this year, at the earliest possible time.<br />Hwang Sung-hee, Arirang News.