The U.S. administration of President Joe Biden plans to keep its North Korea policy flexible, while building on a 2018 summit agreement that included Pyongyang's commitment toward denuclearization, according to a senior official.The Biden administration wants "maximum flexibility" in the process of dealing with Pyongyang, the official said as he explained why the diplomatic strategy on the issue is unlikely to be detailed in public.The remarks were made during a conference call to preview the meeting between Biden and South Korean President Moon Jae In in Washington on Friday, during which …READ FULL ARTICLE