International Day against Nuclear Tests

Since nuclear weapons testing began 80 years ago, over 2,000 have taken place. On the International Day against Nuclear Tests (IDANT), the   United Nations Secretary-General antonio Guterres calls on all States to ratify the Comprehensive Nuclear-Test-Ban Treaty. Its entry into force is more urgent than ever. “Now is the time to silence the bombs before they speak again.”

As we observe the International Day against Nuclear Tests , we are also approaching another milestone. In 2026, we will mark 30 years since Comprehensive Nuclear Test-Ban Treaty was opened for signature . Anniversaries invite reflection, not only on what has been achieved but also on the work that lies ahead. Our Treaty has already had a profound impact. Nuclear test explosions have become extremely rare, and the verification regime operates with global reach and trust. We look forward to the day when Treaty enters into force, enabling all elements of the verification regime to be deployed. Achieving this will require the remaining States to take the final step . They have the opportunity to help complete what was started almost three decades ago. Their decision to ratify the Treaty would reinforce a commitment that has already proved its worth and support a system that benefits every region. This International Day is a reminder that the absence of nuclear test explosions is not a ma...

Today’s international climate is marked by heightened tensions and evolving geopolitical dynamics. However, the record leaves little room for doubt: testing has come to an almost complete halt, and States continue to support and use the verification system . This reflects a near-universal view that nuclear testing has no place in the twenty-first century . The International Day againts Nuclear Tests (IDANT) reminds us that change happens when people understand why it matters. Communities affected by past tests carry voices that deserve to be heard. Diplomats, scientists, educators and youth advocates help translate remembrance into prevention. Their work strengthens a culture of responsibility that maintains the silence we expect from test sites across the world.

The success of the Comprehensive Nuclear-Test-ban Treaty rests on science in the service of diplomacy. Its International Monitoring System (IMS) , already operating with more than 300 stations and laboratories in over 90 countries, uses seismic, hydroacoustic, infrasound and radionuclide technologies to detect any nuclear explosion . Data from this network flow to the International Data Centre in Vienna, where they are processed around the clock and made available to all signatory States. This transparency builds confidence. All States rely on the same objective information to assess adherence to the Treaty and to determine whether a nuclear test has taken place. Even countries that have not yet ratified the Treaty host facilities and benefit from the data. That participation reflects the value and credibility that nations place in a system built through global cooperation. Those benefits extend well beyond peace and security: IMS data contribute to tsunami warning systems, support...

Before the Comprehensive Nuclear-Test-ban Treaty (CTBT) was opened for signature, more than 2,000 nuclear test explosions had been conducted worldwide. Since 1996, that number has fallen to fewer than a dozen. This dramatic decline is no accident. It reflects the strength of the norm created by our Treaty and the value that the international community places on preventing any return to testing . The Treaty is already a proven success. It has brought almost all nuclear testing to an end, placing powerful constraints on the development of new nuclear weapons and the advancement of existing designs , while fostering a strong international expectation that testing belongs in the past . Entry into force will build upon this, giving us the full range of verification measures , including on-site inspections , to further reinforce what has already been achieved.

  Nuclear testing harms the environment , undermines economic development, and has devastating effects on people’s lives and health . It is a relic of another age that has no place in the 21st century. “ My message to leaders is simple: stop playing with fire. Now is the time to silence the bombs before they speak again, ” said UN Secretary-General ‌António Guterres on Friday's August 29th ,observance of the  International Day against Nuclear Tests .