Reigning world heavyweight champion Oleksandr Usyk will "most likely" face off in a rematch with Britain's Anthony Joshua on August 20, Usyk's promoter told AFP on Wednesday.

"This date is the most likely," Oleksandr Krasyuk said of the potential date for the much-anticipated bout.

Usyk defeated then WBA, IBF and WBO champion Joshua last September by a unanimous decision in London.

Joshua immediately voiced his readiness to face Usyk again.

Krasyuk said the fight would most likely be somewhere in "the Middle East" without elaborating.

He added that an official announcement on the bout was due next week by boxing organisations whose belts are at stake.

Usyk, 35, returned to Ukraine to "defend my home" when Russia invaded on February 24.

He left the war-torn country again in March to begin preparations for the rematch.

Usyk was one of several top Ukrainian sports personalities who said they would resist Russia's invasion.

Former world lightweight champion and two-time Olympic gold medallist Vasiliy Lomachenko also returned to help defend his hometown near the southern port city of Odessa.