While nuclear sharing arrangements remove the incentive for NNWS to develop nuclear weapons, thus complementing the non-proliferation objectives of the NPT, the very fact that nuclear weapons have been considered in the security calculus of nations runs contrary to the objective of nuclear disarmament.

In its 2026 National Report to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) Review Conference (RevCon), Russia expressed concerns about the ‘nuclear-sharing’ arrangements in Europe. Russia stated that “nuclear sharing with the broad participation of non-nuclear member States” in Europe was one of the factors that negatively impacted strategic stability and posed a national security threat to Russia.[i] The reference to the ‘nuclear-sharing’ arrangement was missing in Russia’s 2020 National Report to the NPT RevCon. Ironically, Russia has also stationed its nuclear arsenal in neighbouring Belarus, despite criticising Europe’s ‘nuclear-sharing’ arrangements.[ii]

Although debate over the ‘nuclear-sharing’ arrangement is not new and has occurred at previous RevCons, the issue surfaced in the statements of several countries at the Preparatory Committee (PrepCom) for the 11th NPT RevCon. Moreover, the issue gained traction amid major structural changes in Europe regarding ‘nuclear sharing’ since 2025. Therefore, as the international community closely watches developments at the 2026 NPT RevCon, ‘nuclear sharing’ is expected to be a topic of discussion.[iii]

Structural Changes in Europe

The United States (US) nuclear umbrella has been the bedrock of North Atlantic Treaty Organization’s (NATO) security architecture in Europe for years, and the US has binding commitments to defend European allies. However, the US 2026 National Defence Strategy made it clear that the US expected the European countries to take responsibility for European security “with critical but more limited support from the US”.[iv] US President Donald Trump has disparaged NATO and considered withdrawing from it on several occasions.[v] Even the US Secretary of State, Marco Rubio, stated that the US would have to re-examine its relationship with NATO after several European countries denied the US access to their bases during the ongoing Iran War.

The US administration’s stance towards NATO has dented the US’s credibility and its commitments to extend nuclear deterrence to its allies. Thus, France and the United Kingdom (UK) are taking steps towards having an independent European nuclear deterrent, alongside the NATO nuclear mission. France declared the policy of ‘Forward Deterrence’ in March 2026, in response to the Russian security threat to Europe, growing cooperation among Russia, China and North Korea, and the fledgling US commitments to NATO.[vi]

The policy opened the door for European allies to participate in French deterrence exercises and temporarily deploy elements of the French strategic air force to allied countries.[vii] This would help the French strategic air force maintain a presence deep within European territory, creating doubts in the adversary’s mind.[viii] The non-nuclear European nations participating in this initiative are Poland, the Netherlands, Belgium, Greece, Sweden and Denmark, alongside Germany and the UK. However, the decision to employ the nuclear weapon would solely remain with the French President.

Before the announcement of the ‘Forward Deterrence’ policy, France and the UK announced a resolute commitment to nuclear cooperation under the Northwood Declaration in July 2025.[ix] In a joint statement, they affirmed the inseparability of their........

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