Arnold Klein, Michael Jackson's determatologist, was orginally pin-pointed as the man who was the biological father to two of Jackson's children. But now Klein is speaking out denying the accusations.Via UsWeekly:Diane Swayer asked Klein on Good Morning America this morning if he was the biological father of Prince, 12, and Paris, 11.He replied, "Not to the best of my knowledge. But I'm telling you, if push comes to shove, I can't say anything about it...but, to the best of my knowledge, I am not the father of these children.""That's an intriguing phrase, 'to the best of my knowledge,'" Sawyer replied."Yes," he admitted."I can't answer it any other way," Klein went on.On June 30, he released a statement through his lawyer stating he was "aware of media reports" about the paternity but "because of patient confidentiality, Dr. Klein will make no statement on any reports or allegations."In the GMA interview, Klein spoke warmly of the children (Jackson also raised Blanket, 7), calling them "brilliant" and reminiscing about their last Christmas with their father."The kids were so very happy and so beautiful," Klein said. "Every time they would pass their father they would say, 'I love you Daddy.'"Klein last saw Jackson June 22 -- three days before he died of cardiac arrest."He was not in terrible pain when I saw him. He danced in the office, and he danced for my patients," Klein said. "He was very muscular, and he was very, very happy and dancing."I saw nothing at that point that would make me worry whatsoever," he continued. "But I was always concerned about him because I was always worried about other doctors."Klein also denied that he is under investigation for supplying Jackson with any prescription narcotics."I say that anyone who makes someone an addict or gives a person potentially dangerous substances directly to them to use, like [anesthesia] propofol is a criminal," Klein told Good Morning America. "It becomes nothing more than a manslaughter, or something worse than that."There was nothing wrong with the manner I treated Michael, because what I had to do is restructure for an individual who had lupus, who had terrible acne scarring his face," Klein added. "But I was not one of the doctors who participated in giving him overdoses of drugs or too much of anything. In fact, I was the one who limited everything, who stopped everything."Regardless, Klein said, "no matter what he wanted, someone would give it to him. The very rich and the very poor and the very famous all get the worst medical care."