Related Rule
United States of America
Practice Relating to Rule 114. Return of the Remains and Personal Effects of the Dead
Section A. Return of the remains of the dead
The US Field Manual (1956) provides that an Official Graves Registration Service “shall allow … the possible transportation to the home country” of the bodies exhumed. The manual adds that the ashes “shall be kept by the Graves Registration Service until proper disposal thereof in accordance with the wishes of the home country”. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 218.
The Annotated Supplement to the US Naval Handbook (1997) provides that “as soon as circumstances permit, arrangement be made to … facilitate the return of the remains when requested”. 
United States, Annotated Supplement to the Commander’s Handbook on the Law of Naval Operations, prepared by the Oceans Law and Policy Department, Center for Naval Warfare Studies, Naval War College, Newport, Rhode Island, November 1997, § 11.4, footnote 19.
In 1987, the Deputy Legal Adviser of the US Department of State affirmed: “We support … the principle that each party to a conflict permit teams to … facilitate the return of the remains when requested”. 
United States, Remarks of Michael J. Matheson, Deputy Legal Adviser, US Department of State, The Sixth Annual American Red Cross-Washington College of Law Conference on International Humanitarian Law: A Workshop on Customary International Law and the 1977 Protocols Additional to the 1949 Geneva Conventions, American University Journal of International Law and Policy, Vol. 2, 1987, p. 424.