The UN Declaration on the prohibition of the use of nuclear and thermo-nuclear weapons is resolution number 1653 passed by the United Nations General Assembly in its 16th Session in 1961. As such, it is not binding as international law for member states, but serves as a set of principles to prevent the use of nuclear and thermo-nuclear weapons.
Goal: The goal of the Declaration is to prevent any human deaths or suffering that would result from the use of nuclear or thermo-nuclear weapons, in light of the fact that disarmament has not always been successful and that nuclear weapon detonation would have a negative effect on all of mankind.
Relevant Clauses 
1. b) The use of nuclear and thermo-nuclear weapons would exceed even the scope of war and cause indiscriminate suffering and destruction to mankind and civilization and, as such, is contrary to the rules of international law and to the laws of humanity;
c) The use of nuclear and thermo-nuclear weapons is a war directed not against an enemy or enemies alone but also against mankind in general, since the peoples of the world not involved in such a war will be subjected to all the evils generated by the use of such weapons;
d) Any State using nuclear and thermo-nuclear weapons is to be considered as violating the Charter of the United Nations, as acting contrary to the laws of humanity and as committing a crime against mankind and civilization;
United Nations General Assembly (1961). 1653 (XVI) Declaration on the prohibition of the use of nuclear and thermo-nuclear weapons. Retrieved October 14, 2013, from General Assembly Resolutions 16d Session: http://daccess-dds-ny.un.org/doc/RESOLUTION/GEN/NR0/167/06/IMG/NR016706.pdf?OpenElement