Briton Moses Itauma has been ordered by the IBF to hold talks with Cuba’s Frank Sanchez about fighting for the vacant heavyweight title.
Last week Oleksandr Usyk relinquished his IBF, WBA ‘super’ and WBC.
The IBF said that, “in accordance with IBF championship rules”, it now wants Sanchez, who is number one in their heavyweight rankings, to fight number three contender Itauma.
It said: “They have until 29 July to reach an agreement.”
However, 21-year-old Itauma is scheduled to fight Croatia’s Filip Hrgovic at London’s O2 Arena on 29 August in what he has called his “toughest fight”.
Itauma could pull out of the Hrgovic fight or agree to fight Sanchez after that bout.
BBC Sport has contacted Itauma’s promoter Queensberry for comment.
Itauma claimed an impressive fifth-round stoppage over Jermaine Franklin in Manchester in March.
Although the IBF has moved to arrange a bout for the vacant title, the WBC upgraded interim champion Agit Kabayel to champion following Usyk’s decision.
Two-time undisputed heavyweight champion Usyk was required to fight German Kabayel after he was granted an exemption to fight Rico Verhoeven in May, but Usyk is now free to fight any opponent.