Mexico
Practice Relating to the Use of Prohibited Weapons
Mexico’s IHL Guidelines (2009), in a section entitled “Basic rules of conduct in armed conflict”, states: “Do not alter weapons or munitions to inflict greater suffering on the enemy.” 
Mexico, Cartilla de Derecho Internacional Humanitario, Ministry of National Defence, 2009, § 14(l).
In 2010, during a debate in the UN Security Council on the protection of civilians in armed conflict, Mexico stated: “Regarding the use of explosives, the fact that there is no specific ban on the use of certain weapons does not mean that those weapons are permitted.” 
Mexico, Statement by the permanent representative before the UN Security Council, 6427th meeting, UN Doc. S/PV.6427, 22 November 2010, p. 23.