Background and Developments


The 64th session of the United Nations General Assembly declared 29 August the International Day against Nuclear Tests through the unanimous adoption of its resolution 64/35 on 2 December 2009. The Preamble of the resolution emphasizes that "every effort should be made to end nuclear tests in order to avert devastating and harmful effects on the lives and health of people" and that "the end of nuclear tests is one of the key means of achieving the goal of a nuclear-weapon-free world.”

The main mechanism for eradicating nuclear weapons testing is through the Comprehensive Nuclear-Test-Ban Treaty (CTBT). It was adopted by the United Nations General Assembly on 10 September 1996. To date, 183 countries have signed the treaty and 164 have ratified it. For the Treaty to into Force, it must be ratified by several of the States with significant nuclear capabilities.

While the general consensus within the international community is that nuclear weapons testing poses life-threatening risks, there still exists to some degree a mindset of one-upmanship among States and a lingering suspicion of the possibility of clandestine nuclear weapons testing. There is also a concern that if nuclear weapons cannot be tested their reliability may be in jeopardy. However, over the years, science and technology have advanced exponentially boosting the capacity to monitor and verify compliance mechanisms and nuclear weapons proliferation detection. These activities and tracking tools have been initiated and developed by the Comprehensive Nuclear Test-Ban Treaty Organization (CTBTO) Preparatory Commission. Despite the stalled ratification, an increasingly robust public advocacy, including activities and events undertaken on the International Day against Nuclear Tests, is exerting pressure on the powers-that-be to move forward on the signing of the treaty with a view towards the ultimate eradication of nuclear weapons testing.  

At the Conference on Disarmament in July 2015, Acting High Representative for Disarmament Affairs, Mr. Kim Won-soo, appealed to the parties  “to demonstrate flexibility, to devise innovative solutions and, above all, to rebuild the trust necessary to move forward.” There have been visible signs of progress on various fronts by Member States – acting on a multilateral level, bilaterally and through unilateral actions – scientific institutes, civil society and grass roots organizations. The latter two have been driving the momentum to pressure their own Governments and others on rethinking the validity of possessing nuclear weapons.

Nuclear disarmament, which UN Secretary-General Ban Ki-moon has described as a “global public good of the highest order” holds the key to peace and security. The International Day against Nuclear Tests speaks to this important concept. Indeed, the significance of “global public good’ is apparent while reflecting on the threat of nuclear tests and nuclear weapons, and in recent years, the threat of nuclear terrorism. Several international commissions, as well as countless General Assembly resolutions, have endorsed this view, while underscoring the horrific effects of any such use—for humanity, for the world’s economies, and for our natural environment.

One of the most critical contributions to current thinking was provided by the Final Document of the 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) which expressed deep concern at the catastrophic humanitarian consequences of any use of nuclear weapons and reaffirmed the need for all States at all times to comply with applicable international law, including international humanitarian law.

The Preparatory Commission of the CTBTO and its 164 ratifiers vigorously continue to push for the Treaty’s entry into force. The CTBTO’s unique monitoring system, already encompassing nearly 90 per cent of them, provides States with confidence that no nuclear explosion will escape detection.

However, nothing can play as crucial a role in avoiding a nuclear war or nuclear terrorist threat as the total elimination of nuclear weapons. Bringing an irreversible end to nuclear explosions will prevent the further development of nuclear weapons. Various activities to commemorate International Day against Nuclear Tests, as well as efforts throughout the year by nations and civil society build the momentum towards a safe and secure world.


Since the International Day against Nuclear Tests was first declared, there have been a number of significant developments, discussions and initiatives relevant to its goals and objectives as well as conferences convened to elaborate and advance these developments.

2016 developments

On 6 January, the Democratic People’s Republic of Korea (DPRK) conducted its fourth nuclear test. More than three dozen seismic monitoring stations of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) detected the event. In response to this test and to the February space launch using ballistic missile technology by the DPRK, the Security Council adopted resolution 2270 (2016) on 2 March, imposing significant new sanctions.

On 16 January, Implementation Day under the Joint Comprehensive Plan of Action was achieved between the EU/E3+3 and the Islamic Republic of Iran. In accordance with Security Council resolution 2231 (2015), all provisions of past resolutions on the Iran nuclear issue were terminated and all the provisions of annex B to resolution 2231 (2015) entered into force.

On 22-26 February, 2-4 and 9-13 May, and 5, 16- 17 and 19 August, the Open-ended Working Group of the General Assembly taking forward multilateral nuclear disarmament negotiations was held in Geneva to substantively address concrete effective legal measures, legal provisions and norms that will need to be concluded to attain and maintain a world without nuclear weapons and to also substantively address recommendations on other measures that could contribute to taking forward multilateral nuclear disarmament negotiations.  The Working Group adopted, by a vote, a report in which it recommended for the General Assembly to convene a conference in 2017 to negotiate a legally-binding instrument to prohibit nuclear weapons, leading towards their total elimination.

On 31 March and 1 April, the fourth Nuclear Security Summit was held in Washington, D.C.  The summited adopted the Communique and five sets of Action Plans in support of 1) the United Nations, 2) the IAEA, 3) INTERPOL, 4) the Global Initiative to Combat Nuclear Terrorism (CICNT) and 5) the Global Partnership against the Spread of Weapons and Materials of Mass Destruction.

On 10-11 April, the G7 Foreign Ministers' Meeting was held in Hiroshima, Japan. On 11 April, the G7 Foreign Ministers issued a Hiroshima Declaration and visited the Hiroshima Peace Memorial Museum located in Hiroshima Peace Memorial Park and laid a wreath at the Cenotaph for the Atomic Bomb Victims.

On 8 May, the 2005 Amendment to the Convention on the Physical Protection of Nuclear Materials (CPPNM) entered into force.

On 27 May, President Obama visited Hiroshima, Japan, as the first sitting president of the United States, and laid a wreath at the Cenotaph for the Atomic Bomb Victims in Hiroshima Peace Memorial Park.

On 13 June, the CTBTO convened a ministerial meeting in Vienna to commemorate the 20th anniversary of the opening for signature of the Comprehensive Nuclear-Test-Ban Treaty. The meeting brought together leaders and policymakers to discuss, review, and reinvigorate discussions on the Treaty and what is need to make permanent the de facto global moratorium on nuclear tests. 

24 September marks the 20th anniversary of the opening for signature of the CTBT.

2014-2015 developments

On 6 May, 2014, China, France, Russia, the United Kingdom and the United States signed the Protocol to the Treaty on a Central Asian Nuclear-Weapon-Free Zone (CANWFZ) during the NPT Preparatory Committee Meeting in New York.  The Protocol provides legally-binding assurances not to use or threaten to use nuclear weapons against CANWFZ treaty parties and prohibits the five Central Asian states—Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan--from allowing the stationing of nuclear weapons within their territories. France deposited its instrument of ratification of the Protocol on 17 November 2014 and the United Kingdom on 30 January 2015. During the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), both China and Russia announced that they had ratified the Protocol and the United States stated that it had submitted the Protocol the United States Senate for consent to ratification.

The Third Conference of States Parties to the African Nuclear-Weapon-free zone Treaty, also known as the Treaty of Pelindaba, which was held in Addis Ababa, Ethiopia  in  May 2014,   was attended by States Parties to the Treaty of Pelindaba, the IAEA, CTBTO, and Forum for Nuclear Regulatory Bodies in Africa (FNRBA). The Treaty of Pelindaba aims to completely eliminate existing nuclear weapons and prevent their proliferation, as enshrined in the 1968 Treaty on the Non-Proliferation of Nuclear Weapons (NPT). There are currently 39 States Parties to the Treaty of Pelindaba

In November 2014, the CTBTO held its most sophisticated on-site inspection exercise to date in Jordan. The Integrated Field Exercise (IFE14) included over 200 international experts, 150 tons of equipment, and required four years of preparation.

On 8-9 December 2014, the Austrian government hosted the Vienna Conference on the Humanitarian Impact of Nuclear Weapons, the third in a series of conferences, which was attended by 158 states, many international organizations and civil society groups. Victims of nuclear explosions gave testimonies of their experiences. Experts from various fields discussed the consequences of nuclear weapons, the impact of nuclear testing, the risk involved with nuclear weapons use, scenarios of nuclear weapons use and the associated challenges as well as an overview of the norms under existing international law pertaining to the humanitarian consequences of nuclear weapons explosions.  

From 27 April to 22 May 2015, the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) was held at the United Nations in New York. Despite intensive negotiations, the Conference was unable to reach agreement on a Final Document.

From 22-26 June 2015, the CTBTO hosted the CTBT: Science and Technology 2015 Conference (SnT2015) at the Hofburg Palace in Vienna, Austria. It was the fifth in a series of multidisciplinary conferences designed to further enhance the strong relationship between the scientific and technological community and the CTBTO.

On 20 July, 2015 The United Nations Security Council unanimously endorsed the nuclear agreement between Iran and world powers. The resolution allows the lifting of UN sanctions on Iran, while establishing a strong monitoring system of Iran’s nuclear programme.

2013-2014 developments

From 4-5 March 2013, the Norwegian government hosted an international Conference on the Humanitarian Impact of Nuclear Weapons in Oslo. During the conference, representatives of national governments, UN agencies, international organizations, and civil society explored three main topics: the immediate humanitarian impact of a nuclear weapon detonation, the wider impact and longer-term consequences, and the national and international preparedness and response capacity. At the close of the conference, the government of Mexico announced that it would hold a follow-up session to continue exploration and discussion of the topic.

From 24-25 March 2014, 53 world leaders gathered in The Hague for the third Nuclear Security Summit, following previous summits held in Seoul in 2012 and in Washington, D.C. in 2010. At the summit, Japan announced its decision to remove 500 kilograms of highly enriched uranium and plutonium. Additionally, 35 stated signed on to an initiative, Strengthening Nuclear Security Implementation, that will further progress and strengthen nuclear security commitments.

The Second session of the Preparatory Committee for the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) met in Geneva from 22 April–3 May 2013. The meeting allowed States parties to discuss and debate implementation challenges, institutional reform, and the positive developments associated with the NPT. In a joint statement, the five NPT nuclear-weapon states reaffirmed their commitment to nuclear disarmament and general, as well as complete disarmament. Additionally, 80 states co-signed a statement that recognized concerns regarding the catastrophic humanitarian consequences of nuclear weapons.

On 26 September 2013, the sixty-eighth session of the General Assembly convened a High-Level meeting on nuclear disarmament.  A majority of participating states called for additional progress on nuclear disarmament and increased compliance and ratification of the NPT and CTBT. States also emphasized the humanitarian impact inherent in the development, testing, maintenance, and use of nuclear weapons. It was also decided that 26 September be annually observed as the International Day for the Total Elimination of Nuclear Weapons, so that together with the International Day against Nuclear Tests, there would be a redoubling of effort towards a world free of nuclear weapons, the ultimate objective of both Days.

From 13-14 February 2014, delegations from 146 governments met in Nayarit, Mexico for the Second Conference on the Humanitarian Impact of Nuclear Weapons  following the 2013 Oslo Conference. The discussions emphasized the global and long-term consequences of a nuclear weapon detonation, regardless of cause, and the great risk presented by the continued existence of nuclear weapons. Several states participating in the conference called for a treaty banning nuclear weapons as the next step on the road toward nuclear disarmament.

The Third session of the Preparatory Committee for the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) met in New York from 28 April–9 May 2014. The Chairman’s draft recommendations were generally well received by States parties and will be conveyed to the 2015 Review Conference as a Chair’s working paper. The recommendations covered the three pillars of the Treaty, and called for, inter alia, accelerated progress in eliminating nuclear arsenals, the entry into force of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) at an early date, and convening the postponed 2012 Conference on the establishment of a Middle East zone free of weapons of mass destruction. 

2012 developments

The United States hosted the third “P5” Conference in Washington, D.C. in late June of this year in which China, France, Russia, the United Kingdom and the United States discussed cooperation on nuclear non-proliferation and disarmament, establishing a standard form of reporting, transparency and mutual confidence-building measures. The P5 also reaffirmed their continued commitment to promote the Comprehensive Nuclear-Test-Ban Treaty (CTBT) and its universalization.

From 30 April-11 May 2012, the First Preparatory Committee for the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) met in Vienna, Austria. The meeting allowed States to review the operation of the NPT and was the first opportunity since the 2010 adoption of an Action Plan to assess activities carried out by Sates and to consider what could be improved upon. Speaking for the first time in her new capacity as United Nations High Representative for Disarmament Affairs, Angela Kane told the meeting that it is “the review process that helps to sustain the NPT as a living Treaty that is periodically assessed in light of the ever-evolving political and strategic circumstances of our times.”

A follow-up to the 2010 Nuclear Security Summit, which had been convened by US President Barak Obama in Washington DC, the 2012 Nuclear Security Summit took place this past March in Seoul, Korea with expanded participation. World leaders renewed commitments made at the 2010 conference including to continue to use the Work Plan of the Washington Summit as the framework for strengthening nuclear security, and to cooperate internationally on a coherent approach to “ensure the secure peaceful uses of nuclear energy.”

The Conference marking the 45th anniversary of the signing of the Treaty of Ttatelolco took place in Mexico City in February 2012. The Treaty is an agreement among Latin American and Caribbean countries on the prohibition of nuclear weapons in their region. There are now 33 countries participating in this nuclear-weapons-free-zone (NWFZ). As International Atomic Energy Agency (IAEA) Director General Yukiya Amano noted, this treaty was the motivation for several treaties around the world in Africa, Asia and the South Pacific. There are now 133 countries which belong to NWFZs.

2011 developments

From 30 June to 1 July 2011, the five permanent members (P5)– of the UN Security Council, which are also the five nuclear-weapon States, recognized by the Nuclear Non-Proliferation Treaty (NPT) – China, France, the Russian Federation, the United Kingdom and the United States – met in Paris. It was their first follow-up meeting to consider the progress on their commitments made at the May 2010 NPT Review Conference. At the meeting, the five agreed to work together on new confidence-building disarmament initiatives, including a working group on nuclear weapons terminology. Also agreed to was a UK-hosted P5 expert-level meeting to discuss lessons learned from the UK's work with Norway on the verification of nuclear warhead dismantlement. The 2011 meeting was a follow-up to the first ever P5 Conference hosted in London in 2009. Afterwards, the P5 issued a statement that, among other things, reaffirmed the recommendations set out in the Action Plan agreed to in the Final Document of the 2010 Review Conference. It also called on all States parties to the NPT to work together to advance its implementation.

From 20 to 24 June 2011, the IAEA held a five-day Ministerial Conference on Nuclear Safety to identify lessons learned from the nuclear accident at the Fukushima Daiichi Nuclear Power Station in Japan. Under the Presidency of Ambassador Antonio Guerreiro of Brazil, the Conference included address by IAEA Director General Yukiya Amano, who emphasized that implementation was key: “Even the best safety standards are useless unless they are actually implemented. I urge all Member States to make a firm commitment to apply IAEA Safety Standards in practice.” Mr. Sergio Duarte, then High Representative for Disarmament presented an opening day message from UN Secretary-General Ban Ki-moon, in which he said that nuclear safety was an evolving process, involving “technological innovations, improvements in training and oversight mechanism, as well as enhanced disaster preparedness.”

In subsequent plenary sessions, Ministers and heads of delegations delivered national statements. The Conference adopted a Ministerial Declaration that called for improvements in global nuclear safety. The Ministers asked the IAEA Director General to prepare a draft Action Plan to address issues related to nuclear safety, emergency preparedness and response and radiation protection of people and the environment, as well as the international legal framework.

From 8 to 10 June 2011, the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) held a conference in Vienna on science and technologyon science and technology. More than 400 scientists representing 70 countries focused on civil and scientific applications to improve the verification regime's ability to detect clandestine nuclear tests. Additionally, the scientists discussed the CTBTO's monitoring of the 11 March Japanese earthquake and the subsequent emissions from the Fukushima nuclear power plant.

On 31 May 2011, UN Secretary-General Ban Ki-moon was the keynote speaker at a Conference on Promoting the Global Instruments of Non-Proliferation and Disarmament under the theme “the United Nations and the Nuclear Challenge.” Held in New York, it was organized by the Permanent Missions of Japan, Turkey and Poland with assistance from the Stimson Center. The Secretary-General reiterated his call for a world free of nuclear weapons and for strengthening the NPT as the cornerstone for global disarmament, and for bringing into force the Comprehensive Nuclear-Test-Ban Treaty.

On 19 April 2011, the Secretary-General attended the Summit on the Safe and Innovative Use of Nuclear Energy, held in Kiev, Ukraine. In his address he noted that the recent power plant accident in Japan, like the Chernobyl disaster 25 years ago, called for “deep reflection” on the future of nuclear energy. He also stressed the need to build a stronger connection between nuclear safety and nuclear security, noting that while the two are distinct issues, boosting one can bolster the other. “At a time when terrorists and others are seeking nuclear materials and technology, stringent safety systems at nuclear power plants will reinforce efforts to strengthen nuclear security,” he said. “A nuclear power plant that is safer for its community is also one that is more secure for our world.”

On 5 February 2011, the New Strategic Arms Reduction Treaty (New START) entered into force. Signed by Presidents Medvedev and Obama on 8 April 2010 and ratified on 22 December 2010 by the United States and on 26 January 2011 by the Russian Federation, the arms reduction pact strengthens transparency, predictability and cooperation.

2010 developments

On 23 September 2010, marking the 14th anniversary of the opening for signature of the Comprehensive Nuclear-Test-Ban Treaty (CTBT), the Foreign Ministers of Australia, Canada, Finland, France, Japan, Morocco and the Netherlands issued a Joint Ministerial Statement emphasizing the importance of the CTBT as a major instrument in ridding the world of nuclear weapons test explosions and contributing to nuclear disarmament and non-proliferation.

Affirming at the CTBT Fifth Biennial Ministerial Meeting that “Nuclear testing has left a legacy of devastated and uninhabitable landscapes and lasting health and economic effects on local and downwind populations”, UN Secretary-General Ban Ki-moon said that he was willing to meet government officials and parliamentarians to address concerns on the monitoring and verification capacity of the CTBT. In May of 2010, all NPT States Parties committed themselves to work to “achieve the peace and security of a world without nuclear weapons”, characterizing a ban on nuclear testing as “vital.”

2009 developments

On 24 September 2009, a two-day high level conference met to promote the CTBT’s entry into force. On that same day, the UN Security Council discussed nuclear non-proliferation and disarmament at the Heads of State level when it unanimously adopted a resolution calling for stronger efforts to end the proliferation of nuclear weapons.

On 17 June 2009, Japan’s parliament unanimously adopted a call, urging its Government to work harder to establish an effective international inspection system preventing the proliferation of nuclear weapons. President Obama’s declaration on 5 April 2009 in Prague that the United States would pursue the goal of a world free of nuclear weapons deeply stirred the imagination of many around the globe, old and young alike.

On 25 May 2009 the DPRK conducted the most recent nuclear test to date, which was immediately detected by the CTBTO’s monitoring system. On this basis, the test met swift and universal condemnation, including unanimous sanctions by the UN Security Council.

On 1 April 2009, the Presidents of the United States and the Russian Federation made a commitment to a nuclear-weapon-free world and to fulfilling their obligations under Article VI of the NPT. Their pledge to further reductions and limits on their strategic offensive arms was hailed as a new beginning.

Earlier developments

On 24 Oct 2008, in his dynamic Five Point Proposal on Nuclear Disarmament, the UN Secretary-General supported a convention or framework of legal instruments under which the entire world become a nuclear-weapon-free zone.

In 2007, nuclear disarmament received a reinvigorated interest when eminent United States statesmen Henry A. Kissinger, Sam Nunn, William J. Perry and George P. Shultz published an op-ed in The Wall Street Journal about the ideal of a world free of nuclear weapons and how to get there.

These concerns sparked further international dialogue when echoed by other leading world figures from Italy, Germany, France, United Kingdom and Poland through a series of articles published in Le Monde, the International Herald Tribune, Frankfurter Allgemeine Zeitun, NRC Handelsblad, Aftenposten and Gazeta Wyborcza. Norway initiated a dialogue at the governmental level that helped to maintain the momentum of the issue. France and the United Kingdom have both announced stockpile reductions and the latter has committed to beginning a scientific examination of the kind of verification needed to reach a nuclear-weapon-free (NWF) world. The establishment of the International Commission on Nuclear Non-Proliferation and Disarmament by Australia and Japan focused an authoritative international expert review of proposals and recommendations on the issue for future action.

Nuclear-weapon-free zones

In the meantime, the Southern hemisphere of the planet has already become almost entirely one nuclear-weapon-free zone by virtue of regional treaties: the Treaty of Rarotonga, covering the South Pacific, the Treaty of Pelindaba, covering Africa, the Treaty of Bangkok covering Southeast Asia, the Treaty of Tlatelolco, covering Latin America and the Caribbean and the Antarctic Treaty. Recently we have witnessed the entry into force of the Treaty on a Nuclear-Weapon-Free Zone in Central Asia, the first such instrument situated entirely north of the Equator.