Related Rule
Belgium
Practice Relating to Rule 54. Attacks against Objects Indispensable to the Survival of the Civilian Population
Under Belgium’s Law of War Manual (1983), it is prohibited to attack, destroy or render useless objects indispensable to the survival of the civilian population, such as foodstuffs, agricultural areas for the production of foodstuffs, drinking water and drinking water installations. 
Belgium, Droit Pénal et Disciplinaire Militaire et Droit de la Guerre, Deuxième Partie, Droit de la Guerre, Ecole Royale Militaire, par J. Maes, Chargé de cours, Avocat-général près la Cour Militaire, D/1983/1187/029, 1983, p. 28.
At the CDDH, Belgium sponsored a draft article on the prohibition of starvation which contained the rule that it is “forbidden to attack, destroy, remove or render useless, crops, drinking water supplies, irrigation works, livestock, foodstuffs or food producing areas for the purpose of denying them to the enemy or the civilian population”. 
Belgium, Proposal of amendment to Article 48 of the draft Additional Protocol I submitted to the CDDH, Official Records, Vol. III, CDDH/III/67, 19 March 1974, p. 218.
Belgium’s Law of War Manual (1983) states that there is a prohibition to attack, destroy or render useless objects indispensable to the survival of the civilian population, “except if these objects are used by the adversary solely for the sustenance of its armed forces, or if that is not the case, if they serve nonetheless in direct support of military action”. 
Belgium, Droit Pénal et Disciplinaire Militaire et Droit de la Guerre, Deuxième Partie, Droit de la Guerre, Ecole Royale Militaire, par J. Maes, Chargé de cours, Avocat-général près la Cour Militaire, D/1983/1187/029, 1983, p. 28.