Nuclear weapons: At a glance

Nuclear weapon states

There are nine countries in the world that possess nuclear weapons. Between them they hold an estimated 12,705 nuclear warheads, 9,440 of which are thought to be operational.

The House of Commons Library has written a series of papers that briefly examine the nuclear policies, capabilities and modernisation programmes of the nine nuclear weapon states. 

Challenges of transparency 

Transparency is a major challenge, however. Even in the most open of democracies nuclear weapons programmes are largely classified. Information is not widely available and, for those countries motivated either by threat perception or conventional military inferiority, the tendency to exaggerate the extent, or operational nature, of their nuclear arsenals is commonplace.

As a result, there can be significant disparity in the estimates of each state’s active arsenal, reserve stockpiles of operational warheads and those warheads awaiting dismantlement. Information on spending related to nuclear weapons can also be limited. This lack of openness is a particular difficulty in relation to those states that operate outside the framework of the Nuclear Non-Proliferation Treaty (NPT) and the International Atomic Energy Agency.

Library papers 

Overview: where are all the world’s nuclear weapons?, 28 July 2022

Nuclear weapons at a glance: Russia, 29 March 2022

Nuclear weapons at a glance: China, 29 July 2022 

Nuclear weapons at a glance: United States, 28 July 2022  

Nuclear weapons at a glance: United Kingdom, 28 July 2022  

Nuclear weapons at a glance: Israel, 28 July 2022 

Nuclear weapons at a glance: France, 28 July 2022 

Nuclear weapons at a glance: India and Pakistan, 29 July 2022 

Nuclear weapons at a glance: North Korea, 17 May 2022

These papers replace Nuclear Weapons – Country Comparisons, House of Commons Library, 9 October 2017.

They will be updated periodically.

Aspirant/ threshold nuclear states

Over the years various states have been identified as nuclear threshold states, either by default because of the sophistication of their civilian nuclear programmes, or because of their nuclear weapon aspirations.

This series of papers does not examine those countries with a latent nuclear capability. However, they continue to have relevance to the overall nuclear debate.

The following House of Commons Library briefings provide further detail on Iran’s alleged nuclear programme and the status of the Joint Comprehensive Plan of Action (JCPOA):

• Iran’s nuclear programme, 28 June 2022 
• Status of the Iran nuclear deal, 14 October 2021 
• The prospects for the Iran nuclear deal, 18 January 2021
• What now for the Iran nuclear deal?, 15 January 2020 
• The Iran nuclear deal and rising tensions in the Gulf, 1 October 2019