Chris Weidman could defend his Ultimate Fighting Championship middleweight title against Vitor Belfort in a showdown that could be staged in May or July.

UFC CEO Lorenzo Fertitta told ESPN that the two middleweight stars will collide in Las Vegas. However, setting up the fight in Las Vegas could pose a major problem.

Belfort has not fought in the United States since 2011 and speculation has risen that it has something to do with his testosterone replacement therapy (TRT). Belfort has defended his use of TRT a number of times, saying that he is doing it legally.

"I'm able to fight anywhere," Belfort said. "I have done everything by the book. Everybody knows that people cheat, but I don't. I'm very open and very loyal to my principles."

However, it is widely believed that Belfort was not granted TRT exemption in the United States -- the reason why most of his previous fights were held in Brazil.

Weidman expressed concern over Belfort's use of TRT, saying that he is happy with the fight being staged in Las Vegas because he believes the Nevada Athletic Commission will not grant Belfort's therapeutic-use exemptions request.

"I'm happy about fighting in Las Vegas," Weidman told USA Today. "He's fought in Brazil now for the last two years, and obviously he looks like the Hulk now. He's on TRT and he's been caught cheating before for testosterone and I don't know what else. For a guy who is 36 years old to have a lot higher testosterone than me at 29 years old, and I've never taken anything, is really not fair."

The Nevada Athletic Commission and UFC have granted TRT exemptions before, as long as they have been within the allowable limit. But if he would have it his way, Weidman would ban the use of testosterone therapy.

"I'm not a big TRT guy - I don't think TRT belongs in our sport," Weidman said. "I don't like it. I don't have the highest testosterone in the world, and I wouldn't take it. I feel just fine where I'm at. Some people would probably tell me to take testosterone, but I wouldn't do it."