Skip to main content

About the NUTRI project

  • NUTRI is a catalogue of the transparency policies and practices of all nine nuclear-armed states regarding their nuclear arsenals and related facilities. NUTRI data is based on official government sources that have been deliberately released by the respective governments. NUTRI offers objective summaries of the perspectives of the nuclear-armed states. (See below for the inclusion criteria for sources.)

  • The Nuclear Transparency Inventory tracks the disclosures of all nuclear-armed states. Currently, that includes China, France, India, Israel, North Korea, Pakistan, Russia, the United Kingdom, and the United States.

  • The Nuclear Transparency Inventory (NUTRI) aims to support mutual understanding and international dialogue by cataloguing, as objectively as possible, whether, how, and why nuclear-armed states choose to disclose information about their nuclear arsenals, policies, and facilities.

    The goal is to document the disclosures of nuclear-armed states ‘in their own words’, using official government sources, not OSINT or leaked data etc.

    In doing so, NUTRI aims to help address a critical concern, which is that the likelihood of nuclear weapons detonations is increasing, whether in testing or war, due to rapid political, technological, and ecological changes.

  • The Nuclear Transparency Inventory (NUTRI) primarily catalogues deliberate disclosures by nuclear-armed states, using official government sources. (See below for our inclusion criteria.)

    The focus is on the presence or absence of transparency, not the specific capabilities of nuclear arsenals. Where NUTRI provides details on the numbers and types of weapons in various nuclear arsenals, it is to show what the state in question has chosen to disclose, not to provide technical assessments.

    In contrast, most other sources aim to provide detailed estimate of the types, numbers, and statuses of nuclear forces, which are often based on unofficial sources and non-governmental analyses, including open-source intelligence (OSINT).

    As such, we see NUTRI as complementing and adding to existing sources in ways that help broaden and deepen international dialogue around nuclear weapons.

  • NUTRI uses ‘transparency categories’ to organise the analysis of nuclear-armed states’ transparency policies. Each category is one area in which a state might choose to disclose information about its nuclear arsenal and related policies and facilities.

    BASIC defined these categories on the basis of extensive consultations with the nuclear policy community in 2024 and 2025, in which we sought feedback on experts’ priorities regarding access to data on the transparency of nuclear arsenals. We elicited input from dozens of UN member states, think tanks, academia, and other civil society organisations via online surveys, individual interviews, and dedicated events at the 2024 and 2025 Preparatory Committee meetings of the Nuclear Non-Proliferation Treaty (NPT).

    At launch, the NUTRI website addresses twelve transparency categories (see below). Twelve additional categories which will be added later in 2026, for a total of 24.

    1. Number of nuclear warheads
    2. Explosive yield of different nuclear warhead types
    3. Number of nuclear-capable delivery vehicles
    4. Types of nuclear-capable delivery vehicles
    5. Fissile material stocks
    6. Fissile material facilities – types
    7. Doctrine on employment of nuclear weapons
    8. Negative Security Assurances
    9. Integration of AI into nuclear weapons systems
    10. Role of non-nuclear strategic technologies in nuclear doctrine
    11. Pre-notification of space launches, missile tests, and nuclear exercises
    12. Modernisation plans for nuclear arsenal
  • No. The Nuclear Transparency Inventory (NUTRI) does not advocate for specific transparency measures, it catalogues the transparency policies and practices of nuclear-armed states.

    The aim is to support further research and dialogue on nuclear transparency by offering officials, decisionmakers, and analysts a trusted source of objective information on what states say about the nuclear arsenals, and to the extent possible, how and why they say it.

    BASIC’s goal is to offer a simple, interactive reference tool to quickly assess and compare how different governments think about the value and impacts of nuclear transparency.

  • NUTRI is a project of the Non-Proliferation and Disarmament Programme at BASIC.

    We are an independent, non-profit think tank whose mission is to safeguard humanity and Earth’s ecosystem from nuclear risks and interconnected security threats, for generations to come.

    The NUTRI project is funded through the generosity of Global Affairs Canada and the Foreign Ministry of the Netherlands.

  • The Nuclear Transparency Inventory (NUTRI) focuses overwhelmingly on ‘official government sources,’ meaning those that are deliberately disclosed by government representatives in official statements or publications. The aim is to provide hi-fidelity summaries of such sources, including:

    • policy statements
    • press releases
    • public documents
    • speeches by relevant national leaders
    • government working papers
    • defence and security white papers etc.

    This is not an exhaustive list, as each state communicates in different ways about its nuclear arsenal. The sources cited by NUTRI reflect those differences.

    The case of Israel is unique, however, due to the country’s strict policy of opacity regarding its nuclear capabilities. As a result, we have used a modified methodology in the Israeli case. For more on this see the methodology page.

  • To ensure the Nuclear Transparency Inventory (NUTRI) accurately represents the transparency policies and practices of the nuclear-armed states, BASIC engaged nine external experts to conduct the research for the project, one for each country. All of these experts are citizens of, and/or fluent in the official language of, their assigned countries

    Where NUTRI refers to an original source that is not in English and the country in question has provided an official translation, we refer to and cite the translated version provided by that country (for example, the Russian Foreign Ministry publishes its own English-language version of the Russian nuclear doctrine).

  • An inventory is a factual catalogue. This is distinct from an index, which generally  means a system for ranking or scoring items based on specific criteria.

  • The Nuclear Transparency Inventory (NUTRI) only addresses states that have nuclear weapons, and Iran does not have nuclear weapons. This is demonstrated, for example, in the 2025 Annual Threat Assessment of the US Intelligence Community, which represents the unanimous conclusion of all US intelligence agencies.

Definitions

  • For the purposes of NUTRI, we define ‘nuclear transparency’ as the practice of a nuclear-armed state deliberately disclosing information about its nuclear arsenal or related policies and facilities.

  • The goal of NUTRI is to catalogue when and why nuclear-armed states choose to disclose information about their nuclear arsenals and related policies and facilities.

    Disclosures may be ‘public’ (there is no restriction on who can access the information), or ‘selective’ (the information is revealed to a select group e.g. data exchange under the 1988 India-Pakistan ‘Non-Attack Agreement’).

    Formal verification mechanisms are not required for disclosures to qualify as transparency practices.

  • For the purposes of the Nuclear Transparency Inventory (NUTRI), ‘strategic non-nuclear technologies’ refers to advanced military or dual-use technologies that can deliver the type of large scale or ‘strategic’ effects generally ascribed to nuclear weapons, thus impacting nuclear doctrines and related calculations of nuclear-armed states, but without relying on nuclear weapons.

    These technologies may be ‘kinetic’, achieving effects through physical impact with their targets (e.g. hypersonic weapons, highly accurate conventional ballistic or cruise missiles, and anti-satellite capabilities of various kinds, among others), or non-kinetic, achieving effects through the disruption, denial, or manipulation of an adversary’s critical systems (e.g. cyberattacks, electronic warfare, directed energy weapons, satellite jamming & dazzling, among others).

    It should be noted that several nuclear-armed states also include chemical and biological weapons in their definitions of weapons with ‘strategic’ effects.