A/RES/53/77 Page 36 Bearing in mind that the Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on Their Destruction of 197247 and the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction of 199345 have already established legal regimes on the complete prohibition of biological and chemical weapons, respectively, and determined to achieve a nuclear weapons convention on the prohibition of the development, testing, production, stockpiling, loan, transfer, use and threat of use of nuclear weapons and on their destruction, and to conclude such an international convention at an early date, Recognizing that there now exist conditions for the establishment of a world free of nuclear weapons, Bearing in mind paragraph 50 of the Final Document of the Tenth Special Session of the General Assembly,1 the first special session devoted to disarmament, calling for the urgent negotiation of agreements for the cessation of the qualitative improvement and development of nuclear-weapon systems, and for a comprehensive and phased programme with agreed time-frames, wherever feasible, for the progressive and balanced reduction of nuclear weapons and their means of delivery, leading to their ultimate and complete elimination at the earliest possible time, Reiterating the highest priority accorded to nuclear disarmament in the Final Document of the Tenth Special Session of the General Assembly and by the international community, Recognizing that the Comprehensive Nuclear-Test-Ban Treaty26 and any proposed treaty on fissile material for nuclear weapons or other nuclear explosive devices must constitute disarmament measures, and not only non-proliferation measures, and that these measures, together with an international legal instrument on the joint undertaking of no first use of nuclear weapons by the nuclear-weapon States and on adequate security assurances of non-use and non-threat of use of such weapons for non-nuclear-weapon States, respectively, and an international convention prohibiting the use of nuclear weapons, should be integral measures in a programme leading to the total elimination of nuclear weapons with a specified framework of time, Welcoming the entry into force of the Treaty on the Reduction and Limitation of Strategic Offensive Arms,57 to which Belarus, Kazakhstan, the Russian Federation, Ukraine and the United States of America are States parties, Welcoming also the conclusion of the Treaty on Further Reduction and Limitation of Strategic Offensive Arms52 by the Russian Federation and the United States of America and the ratification of that Treaty by the United States of America, and looking forward to the full implementation of the START I57 and START II52 Treaties by the States parties, and to further concrete steps for nuclear disarmament by all the nuclear-weapon States, Noting with appreciation the unilateral measures by the nuclear-weapon States for nuclear arms limitation, and encouraging them to undertake further such measures, 57 The United Nations Disarmament Yearbook, vol. 16: No. E.92.IX.1), appendix II. 1991 (United Nations publication, Sales /...