Règle correspondante
France
Practice Relating to Rule 45. Causing Serious Damage to the Natural Environment
Section B. Environmental modification techniques
France’s LOAC Manual (2001) states:
The Stockholm Convention of 10 December 1976 (ENMOD), which has not been signed by France, prohibits the use of environmental techniques for military or any other hostile purposes. France has not adhered to this convention because it is of the opinion that it contains vague provisions which render its application uncertain, particularly with respect to nuclear dissuasion. 
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. 63.