SEOUL, South Korea (AP) — The U.S. military said Saturday that it was moving "assets" to a U.S. air base near South Korea's capital and to the inter-Korean border to prepare for North Korea's returning of the remains of American soldiers who have been missing since the 1950-53 Korean War.

But U.S. Forces Korea spokesman Col. Chad Carroll denied a report by South Korea's Yonhap news agency that U.S. military vehicles carrying more than 200 caskets were planning to cross into North Korea on Saturday.

North Korea agreed to send home U.S. war remains during the June 12 summit between North Korean leader Kim Jong Un and President Donald Trump.

Carroll said in an email that the U.S.-led U.N. Command was moving "assets" to an American air base in Pyeongtaek, South Korea, south of Seoul, and to the Joint Security Area at the border to prepare for the process, but that plans were "still preliminary."

Earlier Saturday, Yonhap cited an unnamed source as saying that about 30 U.S. military vehicles carrying 215 caskets were expected to cross into the North on Saturday afternoon. Carroll called the report "completely false," but didn't immediately reply to an inquiry about the number of caskets being readied.

Between 1996 and 2005, joint U.S.-North Korea military search teams conducted 33 recovery operations that collected 229 sets of American remains.

But efforts to recover and return 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.