Col. Rob Manning, a Pentagon spokesman, was commenting on North Korean leader Kim Jong-un's promise to repatriate the remains as part of last month's summit agreement with US President Donald Trump.
Manning said he could not provide a timeline, but that the Pentagon is supporting the State Department-led effort to bring back the remains.
"The United Nations Command is prepared to receive those remains. They've been prepared to receive those remains. They're the ones that will then get those remains and repatriate them," the colonel told reporters. "I'd have to defer to the diplomats for any insight on timelines or anything like that, but we are ready to receive those remains."
The UNC oversees the cease-fire that ended the Korean War.
US Defense Secretary Jim Mattis said earlier that the UNC would receive the remains, not the South Korean or US militaries alone, because all 21 nations that fought under the UN flag alongside South Korea and the US lost troops in the conflict.
There was widespread speculation that US Secretary of State Mike Pompeo would return with the remains following his visit to Pyongyang last weekend, but that did not happen.
Once the remains cross the inter-Korean border, they will be moved to the US air base in Osan, south of Seoul, and then to Hickam Air Force Base in Hawaii for forensic identification. (Yonhap)