Oleksandr Usyk has been ordered by the WBO to face New Zealander Joseph Parker in a mandatory heavyweight title defence.
The Ukrainian was crowned undisputed world heavyweight champion on Saturday after beating Daniel Dubois in a fifth-round stoppage at Wembley Stadium.
The victory, sealed when he left the Briton on the canvas with a left-handed punch, secured a 24th professional win for the undefeated 38-year-old, who won back his IBF belt and added it to WBA, WBC and WBO titles.
After becoming undisputed world heavyweight champion for a second time, Usyk mentioned Parker as a possible future opponent.
On Thursday, a letter from the WBO ordered negotiations to take place between Usyk and Parker for a mandatory heavyweight title bout.