Tyson Fury has vowed to "seek and destroy" Anthony Joshua and Deontay Wilder as he aims to emulate Muhammad Ali next year.
Fury has not fought since sensationally beating Wladimir Klitschko in Dusseldorf two years ago to claim the IBF, WBO and WBA heavyweight titles.
The 29-year-old gave up his belts last year amid a battle with mental health issues and had his licence revoked after allegations of a failed drugs test.
British Boxing Board of Control general secretary Robert Smith said Fury's UK Anti-Doping (UKAD) hearing can resume when his legal team agree a date.
A licence will not be reinstated until that hearing has taken place, but the Englishman has called out his compatriot Joshua, the WBA and IBF champion, for a fight which he compared to the Rumble in the Jungle between Ali and George Foreman.
Fury also has his sights on WBC title-holder Deontay Wilder.
He posted a picture of Ali and George Foreman in the ring in 1974 on Instagram and wrote: "This is what's to come! The old champ coming back to fight a man who every1 thinks will ko me, same as Ali vs Forman [sic].
"The stylish Ali vs the mummy Forman! [sic] We all know what happens in this fight! I know you all got me whooped, but I will not lay down or be afraid of some muscles & I have the mentality of a winner a man who has never lost a fight.
"A true champion coming back to claim his thrown [sic], This is my era they are from my time, I must destroy them. AJ & Wilder I'm coming back for you pair my mission is seek & destroy the only thing on my mind is destruction whoever gets in my way will be dealt with accordingly.
"There's only 1 winner & that's the fans! Let's make the heavyweights great again, fight the best in the division, Fury= Lineal champ, Joshua= Ibf-Ibo-wba Wilder= WBC. Parker= Wbo But to be fair Parker is only a young lad & is not on my radar he must gain experience & mature in to a big strong man.
"I hold my destiny in my own hands. May the best man win good luck everyone #letsgetthispartystarted2018_2019 the world will see the best fights & see the true heavyweight king recrowned."