Oleksandr Usyk has vowed to do whatever is necessary to protect his country against Vladimir Putin - even if it means taking a life.
The heavyweight world champion has returned to Kiev after a visit to London and has picked up arms as Putin's invasion continues.
Usyk, along with several of his fellow Ukrainian fighters, have put their careers on hold in order to protect their homeland.
And speaking to CNN from his basement as war rages, he said: "If they will want to take my life, or the lives of my close ones, I will have to do it.
"But I don't want that. I don't want to shoot, I don't want to kill anybody, but if they will be killing me, I will have no choice."
Usyk had been in London with his manager last week to continue negotiations for his rematch with Anthony Joshua.
The second instalment of their heavyweight rivalry had been set to take place in either London or the Middle East in May or June.
But the conflict in Ukraine looks set to delay Joshua's revenge mission.
Usyk was recently pictured in military clothing while armed with a rifle - and he insists he has no fear over the future, only bafflement at Putin's actions.
"Maybe, it'll sound sentimental," he added. "But my soul belongs to the Lord and my body and my honour belong to my country, to my family.
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"So there is no fear, absolutely no fear. There's just bafflement -- how could this be in the 21st century?"
Usyk is currently sheltering with his family and friends, including his three children, as Putin steps up his invasion.
"The bombing around is crazy," he said. "They just bombed the city of Mariupol, one of my friends got a rocket in his roof. [The Russians] are not playing games.
"When there is an air raid alarm, we hide. Of course, it's fun when there are a lot of us here; we're having fun.
"But we're forcing ourselves to have fun." They're trying to keep the mood light for the kids."
