About the treaty to prohibit nuclear weapons

July 7, 2017

On 7 July 2017, the United Nations adopted a landmark agreement to ban nuclear weapons, known officially as the Treaty on the Prohibition of Nuclear Weapons. Here we answer some frequently asked questions about how the treaty will operate.

+ What activities does the treaty prohibit?

The treaty prohibits nations from developing, testing, producing, manufacturing, transferring, possessing, stockpiling, using or threatening to use nuclear weapons. It also prohibits them from assisting, encouraging or inducing anyone to engage in any of those activities. In addition, nations must not allow nuclear weapons to be stationed or deployed on their territory.

+ Is the treaty legally binding?

Yes. The treaty is legally binding on those nations that join it.

+ How many nations must join before it enters into force?

Fifty nations must sign and ratify the treaty before it can enter into legal force. Signing is a relatively simple act performed by the executive branch of a government. Ratifying typically involves a legislative process. Once the treaty has entered force, further nations can join it at any stage.

+ Can a nation that possesses nuclear weapons join the treaty?

Yes. A nation that possesses nuclear weapons can join the treaty, so long as it agrees to remove them from operational status immediately and destroy them in accordance with a legally binding, time-bound plan. It is also required to eliminate its entire nuclear weapon programme, which includes nuclear materials, delivery systems and related facilities.

+ Can a nation that “hosts” nuclear weapons join the treaty?

Yes. A nation that hosts another nation’s nuclear weapons on its territory can join the treaty, so long as it agrees to remove them by a specified deadline.

+ Is it possible to remain in a military alliance with a nuclear-armed nation?

Yes. Nothing in the treaty prevents a nation from being in a military alliance with a nuclear-armed nation, so long as its participation in that alliance in no way involves giving support to nuclear weapons.

+ Will the treaty help victims of the use and testing of nuclear weapons?

Yes. Nations must provide adequate assistance to all victims of the use and testing of nuclear weapons, including medical care, rehabilitation and psychological support. They must also provide for their social and economic inclusion.

The preamble acknowledges the harm suffered as a result of the use and testing of nuclear weapons, including the disproportionate impact of nuclear weapon activities on indigenous peoples. It also recognizes the disproportionate impacts on women and girls.

+ Will the treaty address environments contaminated by nuclear weapons?

Yes. Nations must take measures towards the remediation of environments contaminated as a result of activities related to the use and testing of nuclear weapons. The preamble recognizes the grave implications that nuclear weapons pose for the environment.

+ Will nations meet regularly to discuss implementation of the treaty?

Yes. Once the treaty has entered into force, nations will meet regularly to discuss implementation and take any necessary decisions.

+ Can the treaty ever be amended?

Yes. Any nation under the treaty may propose an amendment. This would then be put to a vote. To be adopted, two-thirds of the nations that have joined the treaty would need to vote in favour of it.

+ What happens if a dispute arises?

If a dispute arises between two or more nations under the treaty, they must consult together with a view to settling the dispute by negotiation or by other peaceful means.

+ Can a nation assert that certain parts of the treaty do not apply to it?

No. The treaty does not allow a nation to make “reservations”. This means that a nation cannot join the treaty and assert that certain provisions of it do not apply to it.

+ Does the treaty establish a secretariat?

No. However, nations could decide at a later stage to establish a secretariat to facilitate implementation of the treaty and promote its norms.

+ Can any nation join the treaty?

Yes. Any nation can join the treaty, whether or not it is a member of the United Nations.

+ Will the treaty exist indefinitely?

Yes. The treaty is permanent in nature.

+ Can a nation withdraw from the treaty?

Yes. In exercising its sovereignty, a nation can withdraw from the treaty. It must provide 12 months’ notice. However, it cannot withdraw if it is involved in an armed conflict.

+ When and where was the treaty negotiated?

The treaty was negotiated at the United Nations in New York from 27 to 31 March and 15 June to 7 July 2017.

+ When was the treaty adopted?

The treaty was adopted on 7 July 2017.

+ Is the treaty available in languages other than English?

Yes. The treaty is available in all six official UN languages: Arabic, Chinese, English, French, Russian and Spanish. Each version is an authentic legal text.

+ Which nations supported the adoption of the treaty?

One hundred and twenty-two (122) nations – almost two-thirds of the total UN membership – voted in favour of adoption of the treaty on 7 July 2017. Only the Netherlands voted against and only Singapore abstained from voting. Other nations did not participate. The supportive nations were:

Afghanistan, Algeria, Angola, Antigua & Barbuda, Argentina, Austria, Azerbaijan, Bahamas, Bahrain, Bangladesh, Belize, Benin, Bhutan, Bolivia, Botswana, Brazil, Brunei, Burkina Faso, Burundi, Cabo Verde, Cambodia, Chad, Chile, Colombia, Congo, Costa Rica, Côte d’Ivoire, Cuba, Cyprus, Djibouti, Dominican Republic, DRC (Congo), Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Ethiopia, Fiji, Gabon, Gambia, Ghana, Grenada, Guatemala, Guinea-Bissau, Guyana, Haiti, Holy See, Honduras, Indonesia, Iran, Iraq, Ireland, Jamaica, Jordan, Kazakhstan, Kenya, Kiribati, Kuwait, Laos, Lebanon, Lesotho, Liberia, Liechtenstein, Madagascar, Malawi, Malaysia, Malta, Marshall Islands, Mauritania, Mauritius, Mexico, Moldova, Mongolia, Morocco, Mozambique, Myanmar, Namibia, Nepal, New Zealand, Nigeria, Oman, Palau, Palestine, Panama, Papua New Guinea, Paraguay, Peru, Philippines, Qatar, Saint Kitts & Nevis, Saint Lucia, Saint Vincent & the Grenadines, Samoa, San Marino, São Tomé & Principe, Saudi Arabia, Senegal, Seychelles, Sierra Leone, Solomon Islands, South Africa, Sri Lanka, Sudan, Suriname, Sweden, Switzerland, Tanzania, Thailand, Timor-Leste, Togo, Tonga, Trinidad & Tobago, Tunisia, Uganda, United Arab Emirates, Uruguay, Vanuatu, Venezuela, Vietnam, Yemen, Zimbabwe.

+ Which nations participated in the negotiations?

One hundred and thirty-five (135) nations participated in the negotiations, according to official records:

Afghanistan, Algeria, Andorra, Angola, Antigua & Barbuda, Argentina, Armenia, Austria, Azerbaijan, Bahamas, Bahrain, Bangladesh, Barbados, Belize, Benin, Bhutan, Bolivia, Botswana, Brazil, Brunei, Burkina Faso, Burundi, Cabo Verde, Cambodia, Cameroon, Chad, Chile, Colombia, Congo, Costa Rica, Côte d’Ivoire, Cuba, Cyprus, Djibouti, Dominican Republic, DRC (Congo), Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Ethiopia, Fiji, Gambia, Ghana, Grenada, Guatemala, Guinea, Guyana, Haiti, Holy See, Honduras, Indonesia, Iran, Iraq, Ireland, Jamaica, Jordan, Kazakhstan, Kenya, Kiribati, Kuwait, Laos, Lebanon, Lesotho, Liberia, Libya, Liechtenstein, Macedonia, Madagascar, Malawi, Malaysia, Malta, Marshall Islands, Mauritania, Mauritius, Mexico, Moldova, Monaco, Mongolia, Morocco, Mozambique, Myanmar, Namibia, Nauru, Nepal, Netherlands, New Zealand, Nicaragua, Nigeria, Oman, Palau, Palestine, Panama, Papua New Guinea, Paraguay, Peru, Philippines, Qatar, Saint Kitts & Nevis, Saint Lucia, Saint Vincent & the Grenadines, Samoa, San Marino, São Tomé & Principe, Saudi Arabia, Senegal, Seychelles, Sierra Leone, Singapore, Solomon Islands, South Africa, Sri Lanka, Sudan, Suriname, Swaziland, Sweden, Switzerland, Syria, Tanzania, Thailand, Timor-Leste, Togo, Tonga, Trinidad & Tobago, Tunisia, Uganda, United Arab Emirates, Uruguay, Vanuatu, Venezuela, Vietnam, Yemen, Zambia, Zimbabwe.

In addition, several nations participated informally. Their officials were never accredited, but they did attend parts of the negotiations. According to ICAN’s records, these nations included:

Central African Republic, Comoros, Dominica, Gabon, Guinea-Bissau, Japan, Kyrgyzstan, Maldives, Mali, Niger, Somalia, South Sudan, Tajikistan, Uzbekistan.



  • aiweiwei

    “Let’s act up! Ban nuclear weapons completely and unconditionally.”

    Ai Weiwei Artist and activist

  • sheen

    “If Gandhi and Martin Luther King Jr were alive today, they would be part of ICAN.”

    Martin Sheen Actor and activist

  • bankimoon

    “I salute ICAN for working with such commitment and creativity.”

    Ban Ki-moon Former UN chief

  • yokoono

    “We can do it together. With your help, our voice will be made still stronger. Imagine peace.”

    Yoko Ono Artist

  • jodywilliams

    “Governments say a nuclear weapons ban is unlikely. Don’t believe it. They said the same about a mine ban treaty.”

    Jody Williams Nobel laureate

  • desmondtutu

    “With your support, we can take ICAN its full distance – all the way to zero nuclear weapons.”

    Desmond Tutu Nobel laureate

  • herbiehancock

    “Because I cannot tolerate these appalling weapons, I whole-heartedly support ICAN.”

    Herbie Hancock Jazz musician

  • dalailama

    “I can imagine a world without nuclear weapons, and I support ICAN.”

    Dalai Lama Nobel laureate