Vienna, 27 June 2022

The Executive Secretary of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), Dr. Robert Floyd, on Monday called on North Korea to renew its 2018 commitment to suspend nuclear testing.

In a statement to Member States at a meeting of the Preparatory Commission of the CTBTO, the Organization’s governing body, Floyd said he remained deeply concerned about recent reports that North Korea might resume nuclear tests.

“While I can assure you of the readiness of our verification regime to detect any nuclear test, I wish to take this opportunity to call on the Democratic People’s Republic of Korea to renew the commitment it made in 2018 to suspend nuclear testing, and to encourage the Democratic People’s Republic of Korea to sign and ratify the Comprehensive Nuclear-Test-Ban Treaty (CTBT),” Floyd said.

The CTBTO’s unique International Monitoring System (IMS) spans the globe using four state-of-the-art technologies to ensure no nuclear explosion can go undetected. Data from more than 300 seismic, infrasound, hydroacoustic and radionuclide stations is provided in near-real time to Member States and analysed at the CTBTO’s International Data Centre at its Vienna headquarters.

The system quickly and accurately detected all six of North Korea’s nuclear tests: in 2006, 2009, 2013, twice in 2016 (January and September) and 2017.


The CTBT bans all nuclear explosions on Earth, everywhere, by everyone, and for all time. Adherence to the Treaty is nearly universal, with 186 signatory states and 172 ratifying states. However, to enter into force, the Treaty must be ratified by all 44 States listed in its Annex 2, for which eight ratifications – including North Korea – are still required.

The CTBT verification regime is designed to detect any nuclear explosion, whether underground, under water or in the atmosphere. Currently, 303 certified IMS facilities are operating around the world, of a total of 337 when the network is complete. The data collected by the IMS can also be used for a wealth of civil and scientific purposes, including disaster mitigation measures such as tsunami warnings and the tracking of radioactive releases from a nuclear accident.

Further resources

Pictures of Dr Floyd addressing the Preparatory Commission can be downloaded at

For more information on the CTBTO, visit, and follow on Twitter @ctbto.


Gill Tudor
Chief of Public Information
T: +43 1 26030 6375
M: +43 699 1459 6375