Règle correspondante
Practice Relating to Rule 17. Choice of Means and Methods of Warfare
Ukraine’s IHL Manual (2004) states: Direction and time of offensive action shall be chosen in order to minimize human casualties and destruction of civilian objects (e.g. fire damage to an enemy military plant after the end of its working hours).
2.4.4. … When choosing weapons one shall consider its capacity and peculiarities of objectives (targets) with a view to preventing excessive damage and destruction. 
Ukraine, Manual on the Application of IHL Rules, Ministry of Defence, 11 September 2004, §§ and 2.4.4.