US nuclear weapons in Belgium

Belgium hosts an estimated 10 to 15 US B61 gravity bombs at Kleine Brogel Air Base under NATO's nuclear sharing arrangements, a role it has filled since the early 1960s. The weapons remain in US custody, guarded by a US munitions support squadron; in wartime, and only after explicit authorization by both the US President and NATO, they would be delivered by Belgian aircraft.

The Belgian Air Component is replacing its F-16s, the assigned dual-capable aircraft for decades, with the F-35A. Belgium's first F-35As arrived in country at Florennes on 13 October 2025; Kleine Brogel is due to receive its first four jets in the first half of 2027, and the F-16s keep the nuclear role until the transition completes, with the fleet planned to serve until 2028. On 18 July 2025 Belgium ordered 11 additional F-35As, taking the planned fleet from 34 to 45 aircraft. The F-35A type was certified by the United States to carry the modernized B61-12 in October 2023, a step announced in March 2024; the B61-12 itself was fully forward deployed across Europe by January 2025.

Belgium participates in NATO's Nuclear Planning Group, and successive governments have reaffirmed the hosting role; recurring parliamentary pushes toward the Treaty on the Prohibition of Nuclear Weapons have not shifted policy.

As a non-nuclear-weapon state party to the NPT, Belgium does not own or control the weapons; NATO's position is that the arrangement predates the treaty and is compatible with it, a reading contested by supporters of the prohibition treaty.

Beyond the US arrangement, Belgium is one of the partners of the "forward deterrence" opened by France on 2 March 2026, under which French nuclear-capable aircraft could be stationed temporarily at allied bases; nine European allies had joined the dialogue by June 2026.