The Russian Foreign Minister has outlined two major red lines that could cause Putin to attack the UK, with experts weighing in on the 'greatest military threat of a generation'
15:35, 11 Dec 2025Updated 16:36, 11 Dec 2025
The UK could be facing the "greatest military threat of a generation". Tensions have continued to rise over the war in Ukraine, with President Volodymyr Zelensky once again ruling out the possibility that his country will hand over territory to Russia. A peace proposal drafted by Washington and Moscow suggested that huge swathes of the country be surrendered to Putin, and that limits could be placed on the Ukrainian military.
The Russian Foreign Minister, Sergei Lavrov, accused the UK and EU of being "openly destructive" towards the peace negotiations, whilst heaping praise on President Trump's efforts. Lavrov also recently said that whilst Russia has no desire to go to war with Europe, there are two major "red lines" that if crossed would cause his country to launch an attack.
"As the President [Putin] emphasised, we have no intention of going to war with Europe," the Foreign Minister said, "We have no such intention. But we will respond to any hostile steps, including the deployment of European military contingents in Ukraine and the expropriation of Russian assets."
His comments came after Russian state TV issued a nuclear threat to the UK following news that a British paratrooper had died in Ukraine.
Putin's propagandists said the presence of British armed forces in Ukraine amounts to a “casus belli” for a nuclear strike on the UK. Leading Russian news anchor Vladimir Solovyov told viewers on his nightly show: “Now a nuclear strike on Britain is inevitable.”
READ MORE: NATO urges 'prepare for war like our grandparents saw' in chilling WW3 warningREAD MORE: Putin torturer sent to round up Ukraine war deserters ‘shot dead in revenge killing’International relations experts weighed in on the comments, with one explaining to the Mirror that these lines drawn in the sand were nothing more than "blunt threats" to Ukraine's allies in Europe, "to let Russia defeat Ukraine, or else."
Two red lines
Professor Anthony Glees from the University of Buckingham told the Mirror, "Neither of these red lines ought in theory to be accepted by Ukraine's European allies, but we must fear today, after Trump's Politico Interview and after the publication of the USA's National Security Strategy, that both probably will."
President Trump recently slammed Europe in his sit-down with Politico, dubbing it a "decaying" continent filled with "weak" countries. He said, "Well it depends," when asked about whether the US plans to remain allies with certain European states, and in the NSS strategy, Washington laid out a distinctly arms-length approach to Europe.
Professor Glees explained that this would leave any military presence in Ukraine from the UK and Europe as "very, very, vulnerable".
"Why both matter is that without NATO military structures in Ukraine, any forces sent by the Coalition of the Willing led by the E3 will be very, very vulnerable. Given our present military weaknesses, I do not, alas, believe that the UK, Germany or France can guarantee they will actually provide boots on the ground to protect Ukraine," the expert said.
Dr Arnab Basu, CEO of Kromek, added that though the UK doesn't currently plan to send troops to Ukraine, "military contact may become unavoidable".
'Unavoidable' military contact
"Although Britain is not currently planning to put combat troops into Ukraine, there are scenarios where military contact may become unavoidable and which may risk triggering aggressive flashpoints," Dr Basu explained. "If a Russian drone strays into NATO airspace again, for example, someone will have to decide whether to shoot it down. Something like this could easily be interpreted as escalation and lead to unanticipated consequences."
The expert pointed out that part of the threat of such red lines drawn by the Russian Foreign Minister is that they can, "in reality," be crossed accidentally, even if both sides were trying to avoid them. "We imagine red lines as clear and deliberate, but in reality, they are often crossed by accident.
"During the Cold War, the world almost blew itself to smithereens on multiple occasions because radars glitched, satellites misread sunlight as missile launches, and leaders forced to make decisions. The same risks exist today," Dr. Basu explained.
Professor Glees added that in his opinion, the UK military is simply not strong enough in its current form to combat what he perceives to be "our gravest hour since the 1930s."
"We are too weak to resist Russia and too weak to resist Trump," said Professor Glees, "even though we know that a peace that allows Putin to win will have the most appalling consequences for Ukraine but also for the whole of Europe, beginning with all the post-1997 NATO states that Putin has insisted must quit the Alliance.
Can't rely on the US
He added that the "days are over, full stop" when the UK and Europe could rely upon the US, or Article Five of NATO, which states that an attack on one member country will be treated as an attack on all.
The expert added that the UK and its allies persuading Trump that "he is wrong" will be key to avoiding potential escalation. "Since we are too weak right now, with more parking enforcement officers than troops in the UK, and Germany only slowly gearing up to mass conscription, we will have to try to persuade Trump he is wrong -as he is - and hope he changes his mind," the expert said.
However, Dr Basu believes that the UK is moving in the right direction to combat its military weaknesses, though he has concerns about the speed at which it could take to resolve, and without "definitive action" we could be headed for a "worst case scenario".
"The UK MOD is saying all the right things about its defensive strategy, as outlined earlier this year in the Strategic Defence Review," Dr Basu said. "But the gears of government and the bureaucracy grind so slowly, that it’s difficult to see much real progress as CEO of a British company.
"They have promised more defence spending, but we are yet to see the benefits. The reality is that the UK, and by extension, the world, faces its greatest military threat of a generation. Failure to take definitive action to prepare for a worst-case scenario could be our greatest mistake."
The Ministry of Defence recently announced that a 28-year-old paratrooper had died during a defensive test in Ukraine, something the MOD dubbed a "tragic accident". Dr Basu said that the incident "is a tragic reminder that British support involves more than providing equipment.
"A small number of specialists work with Ukrainian partners on defensive systems, especially in offering training, including on non-lethal aid such as radiation detectors, which help to protect not just Ukraine, but its European neighbours in the event of either a direct nuclear attack, or an accidental leak from one of the country’s nuclear sites, including Chernobyl, which have come under direct fire over the course of the war."
Professor Glees agreed that the death was "tragic" but pointed out that in his view, in light of the major threats facing the UK, "we cannot afford as a nation to be devastated when our brave soldiers give their lives in the service of liberty. It is tragic and should not be necessary, but we cannot be devastated. It implies that if push came to shove and we were based in Ukraine, we'd clear off at the first whiff of gunshot. That's not deterrence.
"We need to up our game in the UK," he added, "and display our real might with our most modern weaponry and aircraft," during major moments like state visits.