The size of the UK’s nuclear arsenal had been on a downwards trajectory. Britain was set to reduce the number of warheads from 225 in 2010 to 180 by the mid-2020s, a decision made by David Cameron’s coalition government of 2010-15. This downsizing was part of three decades of gradual reductions in the UK’s nuclear arsenal, which included retiring its free-fall nuclear bombs in 1998. Britain now has roughly 195 warheads.
which has changed Britain’s stance on the use of nuclear weapons. The British government is also threatening to use its nuclear arsenal against non-nuclear weapons states that are said to be heading in the direction of acquiring nuclear weapons — or, as the Integrated Review puts it, those states judged to be “in material breach of their non-proliferation obligations”. The UK now reserves the right to use nuclear weapons not only against nuclear threats but against enemies possessing chemical and biological weapons or “emerging technologies that could have a comparable impact”.