The organisation has instructed the heavyweight world champion to begin negotiations with the WBO interim champion for a mandatory title defence.
The two fighters have 30 days to reach an agreement for the clash before the organisation orders purse bid proceedings.
In a notice published on the WBO's website on Thursday (13.03.25), negotiations for a bout between Usyk and Parker were ordered in an email to the respective promoters by the organisation's chairman Luis Batista Salas.
The order read: "Please be advised that the WBO World Championship Committee is hereby ordering the commencement of negotiations between to discharge the WBO mandatory championship obligation in the heavyweight division.
"By virtue of this order, the WBO Interim Championship shall be terminated expeditiously in compliance with our institutional policy of only one world champion per weight class.
"The parties have 30 days to reach terms. Failure to do so will result in this committee ordering purse bid proceedings in accordance with WBO regulations of World Championship Contests."
Parker's promoter David Higgins has "no idea" if the fight with Usyk will materialise but explained that his charge would relish a shot at becoming world champion again.
He told Sky Sports: "We have no idea whether or not it will happen next.
"But I can tell you this. I've spoken to Joseph Parker today and he would love to fight for a world title. He will fight anyone, anywhere for a world title.
"That's his goal, to fight for a world title. Joseph is patiently waiting, keeping fit, and if an opportunity comes to fight for a title, he would love to grab it.
"We'd take it in a heartbeat."