A Russian invasion would turn Ukraine into a "wasteland" and risk the worst bloodshed of any European conflict since the Second World War, Boris Johnson said today.
The UK Prime Minister warned President Putin it would be "futile" to invade due to the scale of Ukraine's resistance - and told MPs: "If Russia pursues this path, many Russian mothers’ sons will not be coming home."
Mr Johnson said he feared Russia was on the brink of a war that would "deserve the condemnation of history" after urgent talks last night with Western allies including the US.
“We cannot bargain away a vision of a Europe whole and free that emerged in those amazing years of 1989 to 1991," Mr Johnson told the UK Parliament.
"We will not reopen that divide by agreeing to overturn the European security order because Russia has placed a gun to Ukraine’s head.”
He added: “If the worst happens and the destructive firepower of the Russian Army were to engulf Ukraine’s towns and cities, I shudder to contemplate the tragedy that would ensue.”
“Ukrainians have every moral and legal right to defend their country and I believe their resistance would be dogged and tenacious, and the bloodshed comparable to the first war in Chechnya, or Bosnia, or any other conflict Europe has endured since 1945.
“No one would gain from such a catastrophe.
“Russia would create a wasteland in a country which, as she continually reminds us, is composed of fellow Slavs, and Russia would never be able to call it peace.”
Previous estimates - which vary dramatically - have put the death toll from the Bosnian war at around 100,000, and the two Chechnyan wars at around 160,000.
Boris Johnson told MPs: "There is nothing new about large and powerful nations using the threat of brute force to terrify reasonable people into giving way to otherwise completely unacceptable demands.
"But if President Putin was to choose the path of bloodshed and destruction, he must realise that it'd be both tragic and futile, and nor should we allow him to believe that he could easily take some smaller portion of Ukraine - to salami-slice - because the resistance would be ferocious."
While Mr Johnson stopped short of saying the UK would send its own troops into such a war, he described the Ukrainians as "determined to fight" and noted they have become "steadily more skilled at guerrilla warfare".
The PM added: "If Russia pursues this path, many Russian mothers' sons will not be coming home.
"The response in the international community would be the same and the pain that would be inflicted on the Russian economy will be the same."
He went on: "The British Army leads the Nato battle group in Estonia and if Russia invades Ukraine, we would look to contribute to any new Nato deployments to protect our allies in Europe."
The Prime Minister met virtually last night with leaders of the US, Italy, Poland, France, Germany, European Council, European Commission, and Nato to discuss Ukraine.
It was agreed that no attack from Russia would be tolerated but that "diplomatic discussions" are the "first priority".
Nato said on Monday that it was putting forces on standby and reinforcing eastern Europe with more ships and fighter jets, in what Russia denounced as Western "hysteria" in response to its build-up of troops on the Ukraine border.
The US Department of Defense in Washington said about 8,500 American troops were put on heightened alert and were awaiting orders to deploy to the region, should Russia invade Ukraine.
Russia denies planning an invasion. But having surrounded Ukraine with forces from the north, east and south, Moscow is now citing the Western response as evidence that Russia is the target, not the instigator, of aggression.
Conservative MP Tom Tugendhat, who chairs the Foreign Affairs Select Committee, warned that the Defence Secretary's support for Ukraine risks being "undermined" if the Government does not tackle "dirty Russian money flowing through our system".
The Prime Minister said: "It it absolutely right that the best way to get attention in the Kremlin and in Moscow generally is to have sanctions that are directed at the individual, like Magnitsky sanctions for instance, but that is what we will be coming forward with as well as sanctions that are directed at companies that are of crucial strategic Russian interest."
Labour leader Sir Keir Starmer said: "For too long the implicit message to Moscow has been that President Putin can do what he likes and the West will do little to respond.
"We must now change course and show Russia that any further aggression will result in severe real world consequences."
He added: "Widespread and hard-hitting sanctions must include cutting Russia's access to the international financial system. Europe's over-reliance on Russian energy supplies is well documented and simply must be addressed, and in Britain we have failed to rid our economic and political systems of the ill-gotten money used to support the Putin regime."
"If we take our obligations to global security seriously we cannot go on allowing ourselves to be the world's laundromat for illicit finance."
