South Korean media reported that the US military plans to send 215 caskets to North Korea through a border village on Saturday so that the North could begin the process of returning the remains of US soldiers who have been missing since the 1950-53 Korean War.
Officials from the United States Forces Korea and South Korea's Defense Ministry did not immediately return calls for comment.
South Korea's Yonhap news agency cited an unnamed source as saying that about 30 US military vehicles carrying the caskets were expected to cross into the North on Saturday afternoon.
North Korea agreed to send home US war remains during a June 12 meeting between North Korean leader Kim Jong Un and President Donald Trump. The leaders agreed to work for the denuclearization of the Korean Peninsula without describing when and how it would occur.
Between 1996 and 2005, joint US-North Korea military search teams conducted 33 recovery operations that collected 229 sets of American remains.
But efforts to recover and return the other remains have stalled for more than a decade because of the North's nuclear weapons development and U.S. claims that the safety of recovery teams it sent during the administration of former President George W. Bush was not sufficiently guaranteed.