Соответствующая норма
Practice Relating to Rule 74. Chemical Weapons
Under Hungary’s Criminal Code (1978), as amended in 1998, employing “chemical weapons and chemical instruments of war” as defined in Article II(1) and (7) of the 1993 Chemical Weapons Convention is a war crime. 
Hungary, Criminal Code, 1978, as amended in 1998, Section 160/A(3)(c).
In 1966, during a debate in the First Committee of the UN General Assembly, Hungary stated:
33. … Fascist Italy had used gas in the 1935–1936 war against Ethiopia, although both parties had accepted the provisions of the Geneva Protocol of 1925. Fascist Germany had used gas with unsurpassed savagery in a campaign of mass genocide. Chemical … weapons were being produced in the present armaments race and some of them were actually being used in the war in Viet-Nam. In a report published by the South Viet-Nam National Liberation Front on 22 July 1966, the Committee for the Denunciation of War Crimes Perpetrated in South Viet-Nam by the United States of America had noted that the 406th mobile unit of the United States Bacterial and Chemical Warfare Institute had been transferred from Japan to South Viet-Nam, and that the number of people killed and poisoned in some of the areas affected by the chemicals used had risen by 30 per cent …
34. … A leading authority on international law [Lassa Oppenheim] had stated that the cumulative effect of customary law, and of the existing instruments such as the 1925 [Geneva Gas] Protocol, was probably such as to render the prohibition legally effective upon practically all States …
35. … Indeed, the use of such mass weapons verged upon genocide …
37. … Accordingly, [the Hungarian] delegation had submitted a draft resolution … in which the General Assembly, after recalling that the Geneva [Gas] Protocol of 1925 had been recognized by many States, would declare that the use of chemical … weapons for the purpose of destroying human beings and the means of their existence constituted an international crime. 
Hungary, Statement before the First Committee of the UN General Assembly, UN Doc. A/C.1/SR.1451, 11 November 1966, §§ 33–35 and 37.