Andrei Kelin told Sky News: “We know each other very well [the] involvement of British experts in [the] training, preparation and execution of violence against Russian infrastructure and the Russian fleet in the Black Sea. We know what has happened.” He claimed that evidence had been handed over to the British ambassador and that “it will be made public very soon”. Kelin added: “This is a warning actually that Britain is very deep in this conflict. It means the situation is getting more and more dangerous.” He also denied that Moscow would use nuclear weapons in the conflict. Asked if Moscow would use a so-called tactical nuclear weapon, he said: “No. The world has every assurance that Russia is not going to use [a] tactical nuclear weapon [the] Ukrainian conflict”. Russia, without providing evidence, has repeatedly blamed the UK for Saturday’s audacious attack, in which a swarm of drones attacked Russia’s Black Sea fleet. Russian officials claimed a Royal Navy unit directed operations from the southern Ukrainian port of Ochakiv. The UK has dismissed it as “false claims on an epic scale”. The Kremlin has also accused the Royal Navy of “directing and coordinating” attacks on the Nord Stream undersea gas pipelines in September. Britain said Moscow was making the accusations to play down its failed military campaign in Ukraine. Meanwhile, the UN nuclear watchdog said it found no sign of undeclared nuclear activity at three sites in Ukraine it inspected at Kiev’s request, in response to Russian claims that work was underway on a “dirty bomb”. “Our technical and scientific assessment of the results we have so far has not shown any sign of undeclared nuclear activities and materials at these three sites,” the International Atomic Energy Agency said, adding that environmental samples taken would be analyzed, Reuters reports. Last week, Russian President Vladimir Putin said that Russia knew “about an incident with the preparation of a so-called ‘dirty bomb’” and that Russia knew “where, in general, it was being prepared.” He did not give details of the alleged plot, which he said involved the possibility of loading a device onto a Tochka-U missile or other tactical missile, detonating it and then “blaming it on Russia.” Kyiv categorically denied the accusations. Dirty bombs use conventional explosives, such as dynamite, placed next to radioactive material, which is then ejected by the force of the explosion. In southern Ukraine, a Russian occupation official said Moscow is likely to withdraw its troops from the west bank of the Dnieper river, marking a massive retreat that, if confirmed, would be a major turning point in the war. Archie Bland and Nimo Omer take you to the top stories and what they mean, free every weekday morning Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. However, Ukrainian officials and Western analysts remained wary of signs that Russia was abandoning the region, and there was silence from senior Moscow officials on what would amount to one of Russia’s most humiliating retreats yet. Kyiv said it was still fighting in the region and was wary that Moscow could set a trap by pretending to withdraw. “Most likely our units, our soldiers, will leave to the left [eastern] bank,” Kirill Stremousov, deputy political administrator of the Kherson region, settled in Russia, told Solovyov Live, a pro-Kremlin online media outlet. The area includes the city of Kherson, the capital of the region of the same name and the only major city Russia has captured intact since its invasion in February. It also includes one side of a massive dam across the Dnieper River, which controls the supply of irrigation water to Crimea, the peninsula that Russia has occupied since 2014. Russia had previously flatly accused its forces of planning to withdraw from the region, one of the most important new conquests that Putin claimed to have annexed to Russia in late September. Speculation was rife on Thursday about whether Russia is indeed withdrawing after photos surfaced online showing the main administrative building in the city of Kherson with the Russian flag no longer flying over it. Ukraine has said these images may be Russian disinformation. Natalia Humeniuk, a spokeswoman for Ukraine’s southern military command, said it could be a Russian trap. “This could be a manifestation of a specific provocation, in order to create the impression that the settlements are abandoned, that it is safe to enter them, while they prepare for street fighting,” he said in televised comments. “We continue to fight, also in the direction of Kherson, despite the fact that the enemy is trying to convince us that they are leaving the settlements and creating the effect of a total evacuation.”