It comes on the same day Putin was cut off mid-sentence during a rally in front of 100,000 supporters in Moscow.
Now the UK’s Prime Minister has predicted the Russian President will fail because he “fatally underestimated the heroism and the resolve of the Ukrainians to fight”.
Russia-Ukraine Crisis: Lviv shelling and evacuation
Mr Johnson spoke about the horrors of the war at the Scottish Conservative conference, in Aberdeen on Friday.
“I am more convinced than ever that Putin will fail,” he said.
“He will fail, because in his catastrophic venture in Ukraine he fatally underestimated the heroism and the resolve of the Ukrainians to fight.
“He underestimated Western unity. And among other things, by the way, he underestimated the passionate commitment of the people in this country to help.”
Elsewhere in the conference, Mr Johnson revealed he has promised President Volodymyr Zelensky he will do more to help Ukraine amid the war with Russia.
Earlier in the day, he had made this vow to the Ukraine leader in their morning call.
The two leaders have been speaking almost every day since Russia began its invasion of Ukraine.
More defensive weapons will be provided to help Ukraine against “pitiless bombardments”, the Prime Minister said.
He told the conference: “From my office, I said we stand with you at a time when your people are facing such horror with such courage.
“When you’re fighting, not just for your lives and your homes – for the cause of democracy and freedom itself.
“We know that we must do more to help. I pledge to you that we will.”
More horrors unfolded in Ukraine as Ukrainian authorities said 1,300 people were trapped in the destroyed theatre in Mariupol.
However, there were reports of 130 survivors who had been rescued from the wreckage.
