Russia is poised to attack Britain – and has singled out a drone factory and a missile company as 'legal targets', it was claimed last night.A senior adviser to Vladimir Putin warned that the 'highest levels of the Russian government' were considering a 'hybrid attack', such as sabotage or arson, rather than an 'outright military strike' that would unleash a response from Nato.In an exclusive interview with The Mail on Sunday, Andrei Fedorov, a former deputy foreign minister of Russia, described the UK as 'evil number one'. Among the Kremlin's targets is a drone factory owned by a British-Ukrainian firm, Ukrspecsystems.Details of the company's premises next to RAF Mildenhall, in West Suffolk, were made public in April alongside five other European firms that make weapons and drones for Ukraine in its war against Russia.On Saturday night, Defence Secretary Wes Streeting said: 'The reckless rhetoric and attempts at intimidation we have seen from the Kremlin in recent weeks reflects the weakness of Putin's position and we will not be intimidated.'This has been a bad year for Putin. The front line has barely moved. Russian casualties continue to mount. The Russian people are paying a heavy price for Putin's war.'It is also in our national interest that Putin's aggression must not be rewarded. The Prime Minister, the Foreign Secretary and I are working together to mobilise support for Ukraine ahead of winter.'Among the Kremlin's targets is a drone factory owned by a British-Ukrainian firm, Ukrspecsystems, which is located next to RAF Mildenhall, in West Suffolk Details of Ukrspecsystems's premises next to RAF Mildenhall, in West Suffolk, were made public in April alongside five other European firms that make weapons and drones for Ukraine in its war against Russia It is understood Putin is angry with Prime Minister Andy Burnham for giving Ukraine blueprints for long-range Storm Shadow missilesThe threat comes as: Bosses of British defence companies have been warned they could be targets of Russian hybrid attacks;A pro-Kremlin war channel suggested that a Nato base in Estonia with at least 900 British troops should be attacked;One of the assassins of Russian defector Alexander Litvinenko plans to hold an anti-UK exhibition opposite the British embassy in Moscow;Britain's ambassador to Russia told officials not to confirm if British weapons are going to Ukraine to prevent an escalation by Putin.On Saturday, Elisabeth Braw, an expert on the Atlantic Council thinktank, said that the point of hybrid attacks is that they put a country like the UK in a dilemma about how to respond.She said: 'I call hybrid threats the defender's dilemma because it really is the defender's dilemma.'How exactly are you supposed to hit back because if you were to use military means, then you would really cause World War Three.'Fedorov, 71, said that the Kremlin would not launch an outright military strike against Britain, a Nato member, because it could lead to the Western alliance launching a collective military response against Russia.But he added: 'The UK is evil number one. After the information that UK-made drones were used against Russian oil refineries, this has become a big anger [sic] in Russian society.'Various experts are calling to punish by strike [sic] the UK, and it will be supported by the majority of Russian citizens.'He said that Putin and his cronies were angry Andy Burnham had handed Ukraine blueprints for long-range Storm Shadow missiles, which have been used previously to strike inside Russia. Earlier this week, Prime Minister Andy Burnham met with Ukrainian President Volodymyr Zelensky in Kyiv Andrei Fedorov, a former deputy foreign minister of Russia, said the Kremlin would not launch an outright military strike against Britain, a Nato member, because it could lead to the Western alliance launching a collective military response against RussiaThe missiles – which have a range of 350 miles – are manufactured by the British arms company MBDA, which employs 4,000 people and has its headquarters in Stevenage, Hertfordshire.Fedorov said of MBDA: 'Many experts in Moscow are saying yes, it's a legal target. Absolutely.' Throughout last week, Russian officials, including the Kremlin spokeswoman Maria Zakharova, threatened Britain with attacks, in response to Mr Burnham's visit to Ukraine.The warnings came despite an unannounced visit to Moscow by the head of the CIA, John Ratcliffe, last Tuesday, where he reportedly warned Russia not to attack a Nato country.Ms Zakharova said: 'Andy Burnham's government understands where this will lead. They should understand this is playing with fire and that the consequences could be unpredictable.'The MoS has also been shown an official memo by Nigel Casey, Britain's ambassador to Moscow, which he sent to Foreign Office staff after Mr Burnham's visit.In the memo, he says Russia is losing its 'narrative' on the Ukraine war, which is leading it to 'step up' hybrid warfare across Europe.He adds: 'In this period of escalation in the war, UK officials, whether speaking on or off the record, [should] stick firmly to our policy of neither confirming nor denying whether UK-supplied weapons are used by Kyiv inside Russia. Defence Secretary Wes Streeting said Britain will 'not be intimidated' by the Kremlin. (Pictured: Mr Streeting Streeting in front of a building damaged by Russian strikes in Ukraine)'Any comments which appear to confirm Russian accusations risk unnecessarily elevating already substantial risks to UK national security.'At a briefing in London last week, Western officials warned that Russia is poised to launch more hybrid attacks across Europe as Ukraine gains the upper hand in the war.One said: 'The Russian appetite to conduct hybrid operations is very clear. Our assessment is that Putin wants to avoid a direct confrontation with Nato.'We need to remain vigilant around hybrid threats. Relations are at a very low ebb between us and them.'Former Tory security minister Tom Tugendhat said: 'These are the desperate words of a regime that is losing the war it started. We will not be bullied. The UK will continue standing shoulder to shoulder with Ukraine.'Nick Timothy, the Tory MP for West Suffolk, whose constituency hosts Ukrspecsystems, said: 'People in Suffolk, like the British people as a whole, will never be intimidated by Russian threats.'Our support for Ukraine – which is the victim of unprovoked Russian aggression – will remain as strong as it has always been.'Last night, it also emerged that a pro-Kremlin Telegram channel, ATO Donetsk – a favourite of Russian troops – called for attacks on the Tapa Nato base in Estonia, where 900 British soldiers are stationed. In a broadcast, the channel said: 'We won't fly over Britain, but the Tapa military base houses about 900 British troops, equipment and ammunition depots.'It's only 150km [93 miles] from Russia. The Baltics are a very convenient target for a show trial.'Since the outbreak of the Ukraine war, Russia has launched several hybrid attacks against the UK. In March 2024, a warehouse in Leyton, East London, storing aid for Ukraine, was burned down. The culprits were hired by Russian mercenary group Wagner.And in June, two men were jailed for a number of arson attacks of homes and a car linked to former prime minister Sir Keir Starmer.Ukrspecsystems declined to comment and MBDA could not be reached.Additional reporting: Mark NicolLitvinenko assassin's anti-Britain campaign 'Poison killer' heads UK hate campaignA Kremlin assassin who poisoned defector Alexander Litvinenko with a radioactive chemical in London is now spearheading an anti-British campaign in Russia.Andrey Lugovoy was one of two spies sent to Britain in 2006 to kill Mr Litvinenko – a former Russian Federal Security Service officer who became a fierce Putin critic.Lugovoy, 56, who denies the poisoning and is now an ultra-loyalist Putin MP, is leading the campaign against Britain. He last week told Russian TV his aim is to portray the country as a 'truly terrifying... enemy'.Lugovoy will hold an anti-British exhibition later this year in a building opposite the UK's embassy in Moscow highlighting 'colonial crimes'.It will be titled 'Britlag' to pun with the Russian word gulag. The assassin who poisoned defector Alexander Litvinenko (pictured) is now spearheading an anti-British campaign in Russia