Related Rule
Practice Relating to Rule 55. Access for Humanitarian Relief to Civilians in Need
Italy’s IHL Manual (1991) states that an occupying power has the obligation to accept the despatch of relief materials (foodstuffs, medicines, clothing) by other States or impartial humanitarian organizations, especially if the occupied population is inadequately supplied. 
Italy, Manuale di diritto umanitario, Introduzione e Volume I, Usi e convenzioni di Guerra, SMD-G-014, Stato Maggiore della Difesa, I Reparto, Ufficio Addestramento e Regolamenti, Rome, 1991, Vol. I, § 48(15).