Fabricio Werdum’s first UFC heavyweight title challenger has not yet been determined, according to UFC President Dana White.

White today hosted a Periscope Q&A session with fans and was asked who will be next for Werdum (20-5-1 MMA, 8-2 UFC) after his stunning upset of Cain Velasquez to win the UFC heavyweight championship at UFC 188.

The UFC boss replied that Junior Dos Santos (17-3 MMA, 11-2 UFC) should be the No. 1 contender, but his current injury woes will prevent him from taking the fight. That means Werdum will face either Andrei Arlovski (24-10 MMA, 13-4 UFC) or Stipe Miocic (13-2 MMA, 7-2 UFC).

“It’s either going to be Stipe or Arlovski,” White said. “Dos Santos should get that fight, I agree. Dos Santos should get that fight, but he’s hurt. So he can’t take it.”

Arlovski, No. 5 in the latest USA TODAY Sports/MMAjunkie MMA heavyweight rankings, has the longest active winning streak in the UFC heavyweight division at six fights. He most recently scored a first-round knockout of Travis Browne at UFC 187 and holds a decision win over Werdum at UFC 70 in April 2007.

Rumors swirled earlier this week that “The Pitbull” had received a call from UFC officials indicating he would fight Werdum at an undetermined date later this year. White said that’s not the case.

“We haven’t made a decision yet,” White said. “We’re still working on the heavyweight title fight. I know there’s reports out there that Arlovski has it, but that’s not true.”

Miocic, No. 4, has won four of his past five UFC bouts and made he clear he wants a title shot after his five-round thrashing of Mark Hunt at UFC Fight Night 65.

Dos Santos, who is ranked highest among the named contenders at No. 3, owns a 70-second knockout win over Werdum. He beat the current champ in his octagon debut at UFC 90 in October 2008 and also defeated Miocic by unanimous decision at UFC on FOX 13 in December.

White did not provide a timetable on when a decision will be made for the next UFC heavyweight championship fight.

For more on the UFC’s schedule, check out the UFC Rumors section of the site.