Verifying the Absence of Nuclear Weapons – Results of a Field
Exercise

One of the first steps toward nuclear disarmament will include separation of nuclear weapons from their delivery systems. In this arrangement nuclear weapons would be transferred to centralized storage facilities located at some distance from the bases where delivery systems are deployed or outside of a certain geographic region. This arrangement can include a verification mechanism that would allow parties to confirm the absence of nuclear weapons at certain storage facilities. To check the viability of this approach the UN Institute of Disarmament Research conducted a verification experiment that included a mockup on-site inspection at a former military facility in Menzingen, Switzerland. The exercise took place on 8 March 2023. The project was supported by the governments of Switzerland, Norway, and the Netherlands. Logistical support for the exercise was provided by the Swiss Armed Forces. The inspection included a visit to the site by an inspection team, accompanied by the host team. The inspection included confirmation of the accuracy of the site diagram, selection of an object of verification to be inspected, an inspection inside the selected object, and confirmation of the non-nuclear nature of objects located inside the object of verification. The non-nuclear nature of objects was confirmed by the means of visual inspection and by radiation measurements. The exercise also included an analysis of satellite imagery of the inspected site (with support of Open Nuclear Network). This paper provides an account of the exercise and discusses the lessons for future verification arrangements learned from the model inspection.