Updated

Brian Williams says he let his ego get the better of him in telling stories that exaggerated his role in reporting news stories.

The NBC anchorman, stripped of his role as "Nightly News" anchor and reassigned to MSNBC, broke his silence on NBC's "Today" show Friday about the episodes that derailed his career. He said it came from a bad place inside of him, that it was "ego-driven, a desire to better my role in a story that I was already in."

"It has been torture looking back," Williams told Matt Lauer on "Today." "I was reading these newspaper stories not liking the person I was reading about." He added, "These statements I made, I own this, I own up to this and I had to go through and see and try to figure out how it happened."

On the Iraq incident, he noted that "I told that story correctly for years before I told it incorrectly."

Lauer pressed Williams on whether he knew he was lying when he made certain statements. "Did you know when you went on 'Nightly News' that you were telling a story that was not true," he asked Williams.

"No, it came from a bad place. It came from a sloppy choice of words. I told stories that were not true over the years…looking back it is very clear I never intended to. It got mixed up, it got turned around in my mind."

Williams said it has been "a time of realization" for him both personally and professionally.

"Looking back it had to have been ego that made me think I had to be sharper, funnier, quicker than anybody else. Put myself closer to the action having been at the action at the beginning."

Williams apologized and said he was a different man as a result.

"What happened is the fall of a whole host of other sins...to put myself in a better light, to appear better than I was...I got it wrong."

He also acknowledged that he "pushed back at first" at the punishment that was given. But he said time has passed and he now accepts it, expressing support for Lester Holt, who filled in during Williams' suspension and on Thursday was named the permanent new anchor of "Nightly News."

"Was it my first choice? No," he said. "Obviously I wanted to return to my old job. I thought we had a good 10-year run."

He said he'll work every day to regain the trust of viewers. "I'd go door-to-door if I could," he said.

The Associated Press contributed to this report.