UFC heavyweight Mark Hunt says the promotion has yet to articulate its exact reasons for pulling him from next month's UFC Fight Night event in Sydney.

Hunt, 43, was scheduled to headline the Nov. 18 event against Marcin Tybura. Two weeks ago, however, the UFC announced Fabricio Werdum would take his place on the card because of "medical concerns."

According to Hunt, the UFC announced the switch before he'd even been informed. He says there's been very little correspondence between him and the promotion, which has his career in limbo.

"A journalist rings me up and says, 'You're not fighting in Sydney,'" Hunt told ESPN. "I had to check to see if it was true. I was really upset by that. I've lost a lot of money on this camp, and losing this fight will cost me over $1 million. I had plans for that money. I have taxes to pay. To hear it from a journalist -- they could have called me themselves.

"And the thing is, I didn't know why they pulled me. I still don't. I've passed all the medicals. I'd like to know the reason I've been put on the sideline."

The UFC has not offered details on its decision to remove Hunt (13-11) and did not immediately respond to requests for comment.

In a recent article in PlayersVoice, Hunt described several medical symptoms he's experienced related to his career, including trouble sleeping, memory loss and slurred speech.

Hunt has since said those comments were "taken out of context," and that the crux of the article was his displeasure with performance-enhancing drug use in the sport. Several of Hunt's previous opponents have failed drug tests, including Brock Lesnar last year.

After the article was published, Hunt says the UFC asked him to undergo additional medical testing. He says he was evaluated by a neurosurgeon and psychologist, both of whom cleared him to fight.

"There's nothing in the results that says I can't fight," Hunt said.

Said UFC president Dana White to TMZ: "Sometimes, you gotta protect these guys from themselves, and that's what we're looking into right now."

Hunt scoffed at that notion.

"The UFC says they're acting for my well-being," he said. "Why did they put me in the Octagon with all these cheaters, then? Why are they letting [Georges St-Pierre] fight again when he's talked about seeing aliens? They just let a guy [lightweight Kevin Lee] fight with a staph infection last week. If they're worried about our well-being, why did they do all that?"

Hunt is currently a plaintiff in an active civil lawsuit against the UFC, White and Lesnar. The suit, which was filed in January in Nevada, accuses the defendants of colluding to allow Lesnar to compete at UFC 200 last year despite a failed drug test. Lesnar tested positive for anti-estrogenic agents and was fined $250,000. He was also suspended one year.

Mark Hunt has filed a civil suit against the UFC, Dana White and former opponent Brock Lesnar. Hunt's grievance stems from a fight he lost to Lesnar, after which it was determined Lesnar failed multiple drug tests. Rey Del Rio/Getty Images

Hunt has fought twice since filing the lawsuit but believes it has a strong impact on this latest conflict.

"I think this is because of the lawsuit, of me trying to get an equal playing field against these steroid users, because it isn't my health," Hunt said.

"They're under contract with me and, thus far, I've done nothing wrong. The contract says I'm supposed to be working, but they've pulled me and I don't see any medical reason why. They haven't fulfilled their side of the contract. What I want to know is, 'Why?'

"They haven't stipulated what I need to do. They've just said, 'Once we get what we need, we'll get back to you.' What? How does that work? I've passed the medicals. If they don't want me fighting, then pay me out of my contract and let me go somewhere else."

Hunt has three fights remaining on an exclusive contract with the UFC.