Heavyweight champion joins Ukraine's military

'My soul belongs to the Lord and my body and my honour belong to my country, to my family'

'So there is no fear, absolutely no fear. There's just bafflement -- how could this be in the 21st century?'

When Ukraine's Oleksandr Usyk beat Anthony Joshua to become the unified heavyweight champion of the world on a late summer evening in London last year, little did he know that six months on he would be fighting a battle for the future of his nation.

Russia's invasion of Ukraine last week happened when Usyk was in London on a promotional visit. Unable to fly directly back to his home in Kyiv, he took a flight to Warsaw and drove 500 miles to Ukraine's capital to re-join his family.

In an interview with CNN from his basement on Wednesday, father of three Usyk confirmed he had joined the city's territorial defence battalion and was ready to fight.

"Maybe, it'll sound sentimental," he said in the CNN interview via manager and translator Egis Klimas.

"But my soul belongs to the Lord and my body and my honour belong to my country, to my family. So there is no fear, absolutely no fear. There's just bafflement -- how could this be in the 21st century?"

"I really don't know when I'm going to be stepping back in the ring. My country and my honour are more important to me than a championship belt."

After Russia began what is described by President Vladimir Putin as 'a special military operation' last week, Usyk posted a message on Instagram imploring Putin to stop the war.

So far similar messages have fallen on deaf ears and the world of sport has united in condemnation of Russia's actions.

Usyk said ordinary Russians had been deceived.

"Russian people don't really know exactly what's going on here," he said. "They're not seeing what's going on. They are victims of their President (Vladimir Putin)."

The 35-year-old, who holds the IBF, WBO and IBO belts, described life living under attack, saying that boxing workouts were helping him remain calm and that trying to lighten the mood with humour was helping his children.

"It has helped me to be calm and mentally prepared," he said. "And it helps me to help others who are panicking and nervous."

"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."

Ukraine's former world heavyweight champions Wladimir Klitschko and his brother Vitali, who is now mayor of Kyiv, have also both vowed to take up arms against invading Russian forces.