Related Rule
United Kingdom of Great Britain and Northern Ireland
Practice Relating to Rule 116. Accounting for the Dead
Section D. Identification of the dead after disposal
The UK Military Manual (1958) provides:
Graves Registration Services must be officially established at the outbreak of hostilities, to allow of exhumations and to ensure the identification of the bodies and their possible transportation to the home country. 
United Kingdom, The Law of War on Land being Part III of the Manual of Military Law, The War Office, HMSO, 1958, § 383.
The UK LOAC Manual (2004) states:
7.33. Where the deceased is in possession of two identity discs, one disc should remain on the body and the other should be sent with his personal effects to the information bureau. If the deceased was in possession of only one identity disc, that disc should remain on the body.
7.37 Exhumation is permitted only (a) in accordance with an agreement on the matters dealt with in paragraph 7.36 [relating to respect for and maintenance of graves]; or (b) in accordance with overriding public necessity (which may include “medical or investigative necessity”). In such circumstances, the authorities of the territory in which the grave sites are situated are required to respect the remains and to give notice to the home state of the intended exhumation together with details of the intended place of re-interment. However, these provisions do not prevent the exhumation of temporary graves for the purpose of moving the remains to permanent graves in dignified, properly maintained cemeteries, such as those of the Commonwealth War Graves Commission. 
United Kingdom, The Manual of the Law of Armed Conflict, Ministry of Defence, 1 July 2004, §§ 7.33 and 7.37.