Anthony Joshua sent a message of support to Oleksandr Usyk after the Ukrainian returned to his native following the Russian invasion.
Usyk defeated Joshua in September to become unified heavyweight champion last year and has since pleaded with Russian President Vladimir Putin to put an end to the invasion of Ukraine.
Joshua is expected to rematch Usyk in June or July with the Tottenham Hotspur Stadium favourites to host it again, according to Eddie Hearn.
However, Usyk is currently more focused on the ongoing conflict between Russia and Ukraine and Joshua is hopeful that 'peace' will be resolved.
"I've learned sports and politics go hand in hand,' Joshua told iFL TV.
"They are powerful voices and it is good they are speaking up.
"They are not pushing for war, they are saying let's find peace so good luck to them."
Usyk was in London last week doing media work to promote his upcoming bout against Joshua and upon his arrival back to Ukraine, he spoke his native tongue and shouted 'no war'.
It's not just Usyk who has been vocal, former heavyweight champion and now the mayor of Kyiv Vitali Klitschko alongside brother Wladimir Klitschko have also vowed to take up arms.
Meanwhile, pound for pound king Vasyl Lomachenko has joined the 'territorial defence battalion' for his hometown of Bilhorod-Dnistrovskyi in the south of Ukraine.
The three-weight world champion posted a photo of himself dressed in military clothing on social media.
"The Belgorod-Dnestrovsky Territorial Defense Battalion has been formed and armed," Lomachenko said.