The UK is estimated to have deployed around 40 of its 225 nuclear warheads, while the US has at least 100 warheads at bases across Europe. France does not provide NATO with its nuclear arsenal because of a long-standing decision to remain independent on deterrence. Both camps now, NATO and Russia, have activated their nuclear forces.

Russia and the US are by far the world’s largest nuclear powers, possessing about 88% of the world’s nuclear arsenal, according to the Federation of American Scientists. The US has about 100 non-strategic B61 nuclear weapons deployed in five European countries, Italy, Germany, Turkey, Belgium and the Netherlands, according to the Bulletin of the Atomic Scientists. Russia has about 1,558 non-strategic nuclear warheads, although nuclear disarmament experts say it is very difficult to say exactly how many because of secrecy.

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