Related Rule
France
Practice Relating to Rule 65. Perfidy
Section F. Simulation of protected status by using the distinctive emblems of the Geneva Conventions
France’s LOAC Summary Note (1992) prohibits perfidy and provides: “It is forbidden to feign a protected status to invite the confidence of the enemy (abuse of distinctive signs and signals such as the Red Cross …).” 
France, Fiche de Synthèse sur les Règles Applicables dans les Conflits Armés, Note No. 432/DEF/EMA/OL.2/NP, Général de Corps d’Armée Voinot (pour l’Amiral Lanxade, Chef d’Etat-major des Armées), 1992, § 4.4.
The Summary Note also states that the “perfidious use of protected signs and signals” is a grave breach of the law of war and a war crime. 
France, Fiche de Synthèse sur les Règles Applicables dans les Conflits Armés, Note No. 432/DEF/EMA/OL.2/NP, Général de Corps d’Armée Voinot (pour l’Amiral Lanxade, Chef d’Etat-major des Armées), 1992, § 3.4.
France’s LOAC Teaching Note (2000) states that the recourse to perfidy is prohibited, “notably the abuse … of distinctive signs, such as the Red Cross”. 
France, Fiche didactique relative au droit des conflits armés, Directive of the Ministry of Defence, 4 January 2000, annexed to the Directive No. 147 of the Ministry of Defence of 4 January 2000, p. 3.
France’s LOAC Manual (2001) states: “The use of these insignia [red cross and red crescent] to deceive the enemy with a fraudulent intent is an act of perfidy. It is prohibited and constitutes a war crime when resulting in death or serious injury.” 
France, Manuel de droit des conflits armés, Ministère de la Défense, Direction des Affaires Juridiques, Sous-Direction du droit international humanitaire et du droit européen, Bureau du droit des conflits armés, 2001, p. 46.
The manual further states that the camouflage of a military activity in a relief operation, such as using an ambulance to permit the passage of combatants through enemy lines or using the red cross to lure the enemy into an ambush, is to be regarded as a war crime. 
France, Manuel de droit des conflits armés, Ministère de la Défense, Direction des Affaires Juridiques, Sous-Direction du droit international humanitaire et du droit européen, Bureau du droit des conflits armés, 2001, pp. 62 and 94.
Generally, the manual considers that using a protective sign to deceive the enemy and reach an operational goal constitutes an act of perfidy, while “the perfidious use of any protective sign recognized by international law constitutes a war crime”. 
France, Manuel de droit des conflits armés, Ministère de la Défense, Direction des Affaires Juridiques, Sous-Direction du droit international humanitaire et du droit européen, Bureau du droit des conflits armés, 2001, pp. 62 and 118; see also p. 115.
France’s Penal Code (1992), as amended in 2010, states in its section on war crimes related to international armed conflict:
Making improper use of … the distinctive emblems provided for under the 1949 Geneva Conventions and their [1977] Additional Protocols, and thereby causing serious bodily harm to a combatant from the adverse party is a punishable offence. 
France, Penal Code, 1992, as amended in 2010, Article 461-29.