North Korea has reportedly completed preparations for the transfer of the remains of American soldiers killed in the Korean War. 

A diplomatic source in Seoul said Thursday that North Korea recently received two truckloads of wooden boxes from the U.S. to be used for the repatriation. 

The source added that the North is expected to hand over the remains on Friday, which marks the 65th anniversary of the signing of the Korean War armistice agreement.

North Korean leader Kim Jong-un promised the repatriation in his summit with U.S. President Donald Trump last month in Singapore. 

Officials from the U.S. Defense POW/MIA Accounting Agency will reportedly visit North Korea to conduct an initial inspection of the remains.

The source said that the U.S. plans to pick up the remains at the North's Kalma Airport along its east coast and move them to Osan Air Base, south of Seoul, by plane. The remains will then be airlifted to a forensic lab in Hawaii.