Prime Minister Boris Johnson announced a dramatic increase in the UK's stockpile of nuclear warheads on Tuesday as he set out plans to overhaul British defence and foreign policy. While the Integrated Review of security and strategic capabilities is set to trigger cuts in troop numbers, tanks and some fighter jets, the nuclear arsenal could potentially increase by more than 40 per cent. The 114-page report was presented to parliament as a wide-ranging re-evaluation of the UK’s security and place in the world since the end of the Cold War. The government warned the country is under threat from rogue states, terrorists and technological advances. As a result British military capabilities and international strategies must be reshaped in response. The decision to bolster nuclear capability reversed the disarmament ethos dating from the end of the Cold War. Other countries are “increasing and diversifying their nuclear arsenals” involving “novel nuclear technologies,” the report said. "In 2010 the government stated an intent to reduce our overall nuclear warhead stockpile ceiling from not more than 225 to not more than 180 by the mid-2020s," the review document said. However, in recognition of the evolving security environment, including the developing range of technological and doctrinal threats, this is no longer possible and the UK will move to an overall nuclear weapon stockpile of no more than 260 warheads. "We have previously identified risks to the UK from major nuclear armed states, emerging nuclear states, and state-sponsored nuclear terrorism. Those risks have not gone away. Some states are now significantly increasing and diversifying their nuclear arsenals. They are investing in novel nuclear technologies and developing new ‘warfighting’ nuclear systems which they are integrating into their military strategies." While it added an assurance that Britain would not use weapons against other members of the Nuclear Non-Proliferation Treaty, the document qualified this committment. "We reserve the right to review this assurance if the future threat of weapons of mass destruction, such as chemical and biological capabilities, or emerging technologies that could have a comparable impact," it said. Mr Johnson said the government needed to address threats through its nuclear and intelligence policies. "The increase in global competition, challenges to the international order, and proliferation of potentially disruptive technologies all pose a threat to strategic stability," the review said. "The UK must ensure potential adversaries can never use their capabilities to threaten us or our Nato Allies. Nor can we allow them to constrain our decision-making in a crisis or to sponsor nuclear terrorism. "The fundamental purpose of our nuclear weapons is to preserve peace, prevent coercion and deter aggression. A minimum, credible, independent nuclear deterrent, assigned to the defence of Nato, remains essential in order to guarantee our security and that of our Allies." Kier Starmer, the leader of the opposition Labour party, said the government was abandoning the domestic political consensus on nuclear weapons and demanded it gave clear reasoning on "when, why and for what strategic purpose" the arsenal would expand. Richard Dannatt, the former head of the Armed Forces, questioned the impact of a costly nuclear build-up, saying that would have consequences for other aspects of defence. "What is the opportunity cost against further developments to some of our conventional capabilities," he said. "We may well find that there are significant cuts to our conventional capabilities. The opportunity cost is what could be done with that money that’s gone on increased nuclear weapons, and where else could it have gone in our defence budget."