WASHINGTON — National Security Adviser Wi Sung-lac said Thursday that he made "progress" in talks with senior U.S. officials over how to accelerate efforts to move forward with the agreements reached in the summits between their leaders. Wi made the remarks on the last day of his two-day trip to Washington after he had meetings with U.S. Secretary of State Marco Rubio, who doubles as the U.S. national security adviser, and Secretary of Energy Chris Wright. "It was good. There has been progress," Wi told Yonhap News TV by phone. "It's difficult to pin down specific areas, (but) we agreed to expedite follow-up measures," he said, without elaborating. South Korea and the United States have released a joint fact sheet outlining their agreements reached between President Lee Jae Myung and U.S. President Donald Trump on trade and security in their two summits in August and October. In the joint fact sheet, the U.S. committed to supporting South Korea for the process that will lead to its civil uranium enrichment and spent fuel reprocessing for peaceful uses. It also includes U.S. approval for