18 HASSAN v. THE UNITED KINGDOM – JUDGMENT the provisions of the present Convention relative to penal and disciplinary sanctions, prisoners of war may not be held in close confinement except where necessary to safeguard their health and then only during the continuation of the circumstances which make such confinement necessary. ... Article 118 of the Third Geneva Convention Prisoners of war shall be released and repatriated without delay after the cessation of active hostilities. ... Article 42 of the Fourth Geneva Convention The internment or placing in assigned residence of protected persons may be ordered only if the security of the Detaining Power makes it absolutely necessary ... Article 43 of the Fourth Geneva Convention Any protected person who has been interned or placed in assigned residence shall be entitled to have such action reconsidered as soon as possible by an appropriate court or administrative board designated by the Detaining Power for that purpose. If the internment or placing in assigned residence is maintained, the court or administrative board shall periodically, and at least twice yearly, give consideration to his or her case, with a view to the favourable amendment of the initial decision, if circumstances permit. Article 78 of the Fourth Geneva Convention If the Occupying Power considers it necessary, for imperative reasons of security, to take safety measures concerning protected persons, it may, at the most, subject them to assigned residence or to internment. Decisions regarding such assigned residence or internment shall be made according to a regular procedure to be prescribed by the Occupying Power in accordance with the provisions of the present Convention. This procedure shall include the right of appeal for the parties concerned. Appeals shall be decided with the least possible delay. In the event of the decision being upheld, it shall be subject to periodical review, if possible every six months, by a competent body set up by the said Power. Protected persons made subject to assigned residence and thus required to leave their homes shall enjoy the full benefit of Article 39 of the present Convention. Article 133(1) of the Fourth Geneva Convention Internment shall cease as soon as possible after the close of hostilities. Article 132(2) of the Fourth Geneva Convention Each interned person shall be released by the Detaining Power as soon as the reasons which necessitated his internment no longer exist. B. The Vienna Convention on the Law of Treaties, 1969, Article 31 34. Article 31 of the Vienna Convention on the Law of Treaties 1969 (“the Vienna Convention”) provides as follows: