Vladimir Putin came alarmingly close to using nuclear weapons in October 2022, prompting then-UK Prime Minister Liz Truss to prepare for potential consequences during her final days in office, according to an updated version of her biography.

Reports indicate that Ms Truss spent her last days as prime minister examining weather maps and preparing for radiation poisoning cases in the UK, following US intelligence suggesting an imminent nuclear strike, The Independent reported.

Ms Truss was reportedly informed that the Russian president was mere hours from deploying a nuclear weapon, which British officials feared could release radioactive material that would spread up to 1,700 miles from the blast. The revised edition of Out of the Blue, an unauthorized biography by journalists Harry Cole and James Heale, claims Truss spent “numerous hours studying satellite weather data and wind directions,” concerned that unfavourable weather patterns could lead to a “direct fallout effect on Britain.”

According to reports, US intelligence indicated a 50 per cent likelihood that Russia might use either a tactical nuclear weapon in Ukraine or a larger bomb over the Black Sea, with the intelligence described as “exquisite.”

Excerpts from Out of the Blue, published by The Sun, reveal disturbing details of how narrowly the war avoided nuclear escalation. On October 18 of that year, then-Defense Secretary Ben Wallace travelled to Washington to address the crisis. Around the same time, President Joe Biden warned of a “direct threat” of Russia using nuclear weapons if the situation continued to escalate, stating, “A nuclear war cannot be won and must never be fought.”

The updated edition of Out of the Blue was released following former Prime Minister Liz Truss’s book, Ten Years to Save the West, which contained striking claims about her 49 days in office.

In her memoir, Ms Truss, who lost her seat in the general election, revealed that upon learning of the Queen’s death, she thought, “Why me, why now?” She also mentioned that Boris Johnson’s dog had left fleas in No. 10, recounting how her husband predicted that her time as prime minister “would all end in tears.”

Ms Truss described learning about Johnson’s forced resignation while she was in Bali as foreign secretary. She recalled, “As I walked along the beach in Indonesia, I started crying. Even Hugh [her husband], who had foreseen it ending in tears, agreed that this was the moment I was expected to step up. If I didn’t, people would say I had backed down.”