The tangible prospect of defeat in Ukraine has increased the likelihood of Russia using nuclear weapons in the conflict, a former British general said. Gen Sir Richard Barrons said it was “likely” that Russian President Vladimir Putin would make the fraught decision to order a <a href="https://www.thenationalnews.com/world/europe/2022/07/27/russia-has-definitively-lost-initiative-in-ukraine/">devastating attack </a>to ward off military disaster for his country. Moscow would probably use a 10-kilotonne warhead set on an Iskander missile, he said, creating a massive fireball incinerating people and buildings within 150 metres of ground zero, while causing third-degree burns within a 1.6-kilometre radius. Kyiv’s forces recent gains, especially around the Russian-held city of Kherson, have raised the possibility of Russia facing “catastrophic success for Ukraine”, Sir Richard wrote in <i>The Times</i>, but if “Putin senses strategic defeat, he is likely to employ tactical nuclear weapons”. A nuclear attack would “break an enormous taboo”, being the first use of the weapons since the US dropped two atom bombs on Japan in 1945, but it was not “inconceivable to Russians if the ends justify it in their eyes”. The Hiroshima blast stemmed from a 15-kilotonne bomb that killed 146,000 people. The potential for a “catastrophic miscalculation” by Moscow could come as early as spring next year if its forces were being pushed out of Ukraine, said the former head of Britain’s Joint Forces Command. The retired officer’s warning comes after concerns raised by western officials, who told <i>The National</i> late last month that “Russia had definitively lost the initiative” and faced with defeat had “other tools available which it could choose to employ which would escalate the situation”. “It comes down to how threatened the Russian state feels,” Sir Richard said. “The more threatened or cornered it becomes, the more likely it will be to reach for essentially the types of tools [nuclear weapons] that you're talking about.” Sir Richard wrote that Russian doctrine was to use small nuclear weapons “to impose unacceptable damage on an opponent as a means of coercion”, particularly when “the existence of the state is in question”. To avoid the nuclear radiation from a ground detonation, it would likely be an air blast from 700 metres that fired over a town such as Kramatorsk would create a fatal radiation dose to anyone within 1km. The blast would collapse buildings, cause third-degree burns to anyone within 1.6km and smash windows at 4km. A warhead could also be dropped on a Ukrainian brigade of up to 5,000 personnel, causing mass casualties. While a nuclear strike would “create great sense of peril around the world”, a smaller device would “not physically touch areas beyond the borders of Ukraine”, Sir Richard said. “These weapons exist for just the sort of circumstances the war in Ukraine may lead to, so nobody should claim total surprise if they are used.” Were such a devastating assault to materialise, defence alliance Nato might escalate efforts to remove Mr Putin from power. While it was unlikely to lead to all-out nuclear Armageddon between the great powers, Sir Richard warned it could lead to countries such as India and Pakistan becoming more willing to use nuclear weapons on each other.