Boris Johnson has compared Vladimir Putin to "the fat boy in Dickens" who wants to "make our flesh creep" with threats of using nuclear weapons.
Speaking at a breakfast event on Ukraine at the World Economic Forum in Davos, the former prime minister said: "Putin wants to present it as a nuclear stand-off between between Nato and Russia.
"Nonsense. He's not going to use nuclear weapons, okay. He's like the fat boy in Dickens, he wants to make our flesh creep. He wants us to think about it. He's never going to do it."
He said such a move would put the Russian president into "a complete economic cryogenic paralysis" and "terrify the Russians".
"He's not going to do it. Don't go down that rabbit hole, stop it," Mr Johnson added.
The ex-PM also also urged the audience to "stop worrying about Kremlinology," quipping: "It's difficult to work out what's gonna happen in UK politics, let alone in the Kremlin."
Yesterday, Putin was heard rambling about the Great Patriotic War - Russia's name for WWII - after a helicopter crash killed 18 in Ukraine just hours before.
The Russian President spoke about Russia's role in World War II shortly after a helicopter ploughed into a kindergarten in Kyiv, killing 18 including Ukraine's interior minister and three children.
Interior Minister Denys Monastyrskyi became the most senior Ukrainian politician killed during the war today when an emergency services chopper crashed in Brovary, an eastern suburb of Kyiv.
His fellow passengers, Deputy Yevhen Yenin and State Secretary of the Ministry of Internal Affairs Yurii Lubkovych were also killed in the explosion, according to Ukraine's national chief of police. Another six people on board also died.
As the helicopter came hurtling to the ground, it smashed into a kindergarten, slaughtering three kids and adults bringing their little ones to school.
A total of 29 people were injured, including 15 children, the regional governor said.
But as emergency responders trawled through the bloody debris, twisted despot Putin was bragging about a Russian city's victory over the Nazis 80 years ago today.
During a meeting with veterans of the "Great Patriotic War" as well as residents alive during the siege of Leningrad. Adolf Hitler's troops besieged the town for a gruelling 872 days, killing one million Red Army soldiers and civilians.
In early 1943, Soviet offensives punched holes in the German blockade circling the city, allowing more supplies to reach Leningrad. Another offensive in 1943 pushed them back completely and effectively ended the siege.
Putin said: “We talked [during the inspection of the exhibition] about what and how happened in the most difficult months of the defence of Leningrad, how heroic its defenders were and what the inhabitants of besieged Leningrad did to defeat the enemy.
"These are all things that will forever remain in the memory of the people of our country, and we, in turn, must pass on this information, these pages of our history to future generations so that it remains forever in the memory of the people."
