The rapper declared that the Twilight actress has committed "career suicide" by incurring the wrath of Robert Pattinson fans through her 'fling' with Rupert Sanders.
"Being a cheating sl*tbag aside i actually feel sorry for Kristen Stewart," he wrote on Twitter. "She may as well have cheated on justin bieber. #careersuicide."
Green's comment comes mere days after he attracted criticism for tweeting that bulimia is "an intelligent eating disorder".
It has been reported that Stewart's fling with her Snow White and the Huntsman director went on for months, though others have claimed that the pair did not even have sex.
Sanders has allegedly been forgiven by his wife Liberty Ross, but Stewart and Pattinson are apparently not speaking and moving vans were spotted outside their California home this week.
Stewart has been described as "the most hated woman in Hollywood" after cheating on Pattinson, with a studio source predicting: "It's going to be a long road for her to come back, professionally as well as personally."