Georges St. Pierre has no interest in a comeback until UFC is clean. (USATSI)

Former Ultimate Fighting Championship welterweight champion Georges St. Pierre said he won't return to the sport unless he knows the fighters are clean, according to mmafighting.com.

I am not surprised to hear that a lot of guys got busted. There is going to be another name coming up. That's what you guys don't understand. If they keep doing the right testing. I am not a rat, I won't say any names; I just wanted to change the system. It shows now that we got a big problem and they need to do something. 

St. Pierre admitted he occasionally gets the itch to return when he watches matches, but stressed that he's not ready to make a comeback yet. "I am not saying I am making a comeback, but I am not interested to compete if the sport is not clean, that is one of my major concerns."

St. Pierre also addressed Anderson Silva's recent positive drug test. While he still considers Silva as the best pound-for-pound fighter out there, St. Pierre said the situation was "unfortunate for his reputation and his health."

UFC President Dana White actually offered St. Pierre a fight with Silva following Silva's win over Nick Diaz, but St. Pierre turned him down. While the offer was made before Silva's test was revelaed, St. Pierre explained that it wasn't the right time for him to return. "Now is not the time for me," he said. "I am not interested right now."

UFC has allegedly worked harder to enforce more strict testing for PEDs recently, but St. Pierre needs to see better results before he's ready to make a comeback.