Wladimir Klitschko, Boxing Champion-Turned-Ukraine Defender, Says, 'This Is the Fight of My Life'

Wladimir Klitschko, Boxing Champion-Turned-Ukraine Defender, Says, 'This Is the Fight of My Life'

Millions of boxing fans have watched Wladimir Klitschko, former heavyweight champion of the world, knock out opponents in the ring.

But "Dr. Steelhammer" says none of that compares to what he's doing now to defend his beloved Ukraine from an ongoing Russian invasion.

"I've been a fighter, but this is the fight," he tells PEOPLE in a recent video interview. "This is the fight of my life. This is the fight of the life of millions of us."

Ukraine has been an independent nation since 1991, when the Soviet Union broke up — though years of Russian interference and the 2014 annexation of the Crimean Peninsula have meant years of struggle. But never has Russia gone this far, launching a large-scale attack on Feb. 24 that has so far killed hundreds and caused millions more to flee.

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"Imperialism of Russia and their leader President Putin, is just to get back to USSR [the Sovier Union], which is not going to happen," Klitschko says.

After invading Ukraine weeks ago, the Russian army has been attempting to encircle the capital, Kyiv, where Klitschko, 45, serves in a defense unit.

They've partially succeeded, he says. "If we're going to be circled by the Russian army, that's it," he says. Even humanitarian aid may not come through. Still, Klitschko says, they won't break.

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Vitali Klitschko, Wladimir Klitschko
Vitali Klitschko, Wladimir Klitschko

ARIS MESSINIS/AFP via Getty Images From left: Vitali Klitschko, mayor of Kyiv, Ukraine, and his brother, Wladimir Klitschko, walk in front of a destroyed apartment building in Kyiv on Monday amid the Russian invasion.

"We're 45 million Ukrainians, we're going to resist, as we do now," he says. "As you see in pictures, in the cities, where they got into the city, people demonstrating with Ukrainian flags, standing in front of the tanks and saying, 'Go home, f-off. This is not your land.' "

In the face of the stronger invading force, but perhaps heartened by his country's resistance so far, Klitschko vows: "There are no Russian tanks — there are never going to be — in the city of Kyiv. The city is strong, people are strong, the will is strong."

He marvels at the unity and resolve he has seen. (Some outside experts have argued Vladimir Putin's attack had the unintended effect of solidifying a shared identity in the 30-year-old nation.)

"I call it amazing because the human spirit, without any negotiation in advance, coordination in advance, agreement in advance, anything in advance that possibly human minds can create together, it wasn't even there," Klitschko says. "It's just like something that connects our minds that we stand against this aggression and this war. And it's just — I haven't seen it. It's just amazing to observe how human side can be so strong."

At the same time, he is bewildered by Russia. "It's obnoxious to see how possibly human mind can do something that Russian army is doing now, while we're talking, and killing Ukrainians. It's just unimaginable and has no sense and no understanding," he says.

One Russian pilot who was shot down and captured had dropped bombs on his mother's own neighborhood because he was commanded to do it, Klitschko claims.

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Kyiv's Mayor Vitali Klitschko
Kyiv's Mayor Vitali Klitschko

GENYA SAVILOV/AFP via Getty Kyiv, Ukraine, Mayor Vitali Klitschko

"He was bombarding his mother," Klitschko says in disbelief. The pilot "got the task and he saw that he needs to bombard districts where people are living in the city, and he knew that he was going to kill the innocent. He dropped the bombs because that was his task. They know what they do. They're just getting these commands to do it."

Klitschko goes on: "It reminds me, if someone is calling Ukrainians Nazi" — Putin insists he is attempting to free Ukraine from alleged Nazi influence — "it's the other way around."

More than two weeks into their invasion, the Russian army has not taken over the capital. In many ways, despite the mounting threats, the city is still functioning thanks to Klitschko's older brother, Vitali, 50, also a former world heavyweight boxing champion, now mayor of Kyiv.

Yet Klitschko says he can hear sirens, launching rockets and explosions day and night. Half of the city's residents have fled and the rest hide in undergrounds and basements, he says.

Klitschko's eyes can only open half way; there is no sleep. Satellite cities a few miles from Kyiv have been destroyed.

"There are human bodies on the ground that no one picks up, it's just too many dead. Too many," he says. "This is brutal war. It's unimaginable what is happening here. This is hell."

"I haven't, in my worst dreams, thought that Russians can do anything like that to Ukrainians," he says, noting that his mother is Russian and his father is Ukrainian. He was born in Kazakhstan when it was part of the Soviet Union and speaks Russian and Ukrainian, as do many others. He still has relatives and friends in Russia.

"With this war, senseless war, the world is not the same any more," he says. Among his fears is the possibility of damage to one of the country's four large nuclear power plants, some of which have already been caught in the cross-hairs.

"Those power plants are gigantic," he says. "That's why this war must be stopped. Now."

Wladimir Klitschko
Wladimir Klitschko

Sascha Steinbach/Bongarts/Getty Wladimir Klitschko

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WLADIMIR KLITSCHKO
WLADIMIR KLITSCHKO

Sandra Behne/Bongarts/Getty Wladimir Klitschko in 2001

Aside from territorial defense, the boxer-turned-resistance fighter has been addressing the outside world, asking for help. As a superstar in his corner of the sports world (who also has an endurance and health foods brand), he has been able to raise about $109 million and counting in the past two weeks for humanitarian aid and medical supplies, he says.

Before the invasion, Klitschko was living part-time in Ukraine and part-time in Germany and Los Angeles. He has custody of his 7-year-old daughter, Kaya, whom he shares with ex-girlfriend Hayden Panettiere.

Klitschko says Kaya was in Ukraine when the war broke out but is no longer in danger. He declined to say how he got her out of the country but says he's still in touch with her — though he worries that will not continue if the internet fails.

Panettiere, who said on social media recently that Kaya was "safe and not in Ukraine" has created a charity, Hoplon International, to send body armor, medical kits and other supplies to the resistance in Ukraine.

"We are together in this, against the Russian aggression," Klitschko says of his ex's efforts.

He says he is thankful for the aid that has come from outside Ukraine but feels much more is needed.

While NATO countries said they could not join the battle and declined to close the air space over Ukraine, fearing their involvement could broaden the war to more countries, Klitschko is pressing forward.

"We're going to take care ourselves. We don't need any army here, we're going to take care with our own army. What we need [is] protective weapons, military equipment," he says, pleading for haste. "We cannot count in weeks. We're counting in minutes and hours. That's how we count."

The Russian attack on Ukraine is an evolving story, with information changing quickly. Follow PEOPLE's complete coverage of the war here, including stories from citizens on the ground and ways to help.