Klitschko brothers have message for Russia, Vladimir Putin: 'We are not going to surrender'

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Vitali Klitschko, the Kyiv mayor and former heavyweight boxing champion, told Reuters Thursday that Ukrainians will continue to defend their homeland from Russian President Vladimir Putin and Russian invaders.

Klitschko was joined by brother Wladimir during a Skype interview with the outlet.

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Vitali Klitschko, Kyiv Mayor and former heavyweight champion, right, and his brother Wladimir Klitschko, a Ukrainian former professional boxer look at a smartphone in City Hall in Kyiv, Ukraine, Feb. 27, 2022. (AP Photo/Efrem Lukatsky)

"Thousands, already tens of thousands, are killed in this war against Ukraine. And this number will unfortunately only grow," Vitali Klitschko said while speaking from a shelter he is working from in Kyiv.

"We are not going to surrender. We have nowhere to retreat."

Klitschko said only about half of Kyiv’s population remains, and authorities helped many orphans leave for Poland and Germany.

"The situation is tense, people are worried," Klitschko said. "The city needs peace and peaceful skies … Kyiv residents have been in their basements nonstop for a week now because of air raid alarm going off all the time."

Vitali Klitschko, Kyiv Mayor and former heavyweight champion, gestures while speaking during his interview with the Associated Press in his office in City Hall in Kyiv, Ukraine, Feb. 27, 2022.  (AP Photo/Efrem Lukatsky)

Klitschko acknowledged that Russia was attempting to seize Kyiv, and he called on Russians to challenge Putin.

"You are an instrument at the hands of one man with one ambition – to resurrect the Soviet Union ... For ambitions of one man, we are