Tyler's departure comes as his fellow judge, Jennifer Lopez, also weighs whether to return to the program that once reigned supreme atop U.S. TV ratings but has seen its audience shrink in recent years. Third panelist Randy Jackson seems a likely bet to return this fall for the program's 12th season as either a judge or in a mentoring role.

"I strayed from my first love, Aerosmith, and I'm back," the band's lead singer said in a statement.

"I've decided it's time for me to let go of my mistress ‘American Idol' before she boils my rabbit," Tyler added, in a reference to the thriller movie, "Fatal Attraction." "I got two fists in the air, and I'm kicking the door open with my band."

Tyler, 64, and Aerosmith had amassed numerous hits like "Walk This Way" and "I Don't Want To Miss a Thing" since gaining fame in the 1970s, but the group had reached a lull a few years back when the singer decided to join "American Idol" as a judge.

The addition of Tyler and Lopez to the judging panel in the season that began in January 2011 sparked great interest in the Fox TV network's hit show.

But the most recent season that ended in May had the lowest-rated finale in 11 years with just 21.5 million Americans tuning in to watch Phillip Phillips win the title and recording contract that comes with it. More than 30 million viewers watched the show's finale in its heyday in 2006 and 2007.

Mark Darnell, president of alternative entertainment for Fox, called Tyler "a terrific judge, a true friend, and great mentor" on the show.

"We are very sad that Steven has chosen to focus more on his music, but we always knew when we hired a rock 'n roll legend, he would go back to music," Darnell said in a statement.

Indeed, Tyler's return to performing seemed foremost on his mind in March when Aerosmith announced it would go on a North American tour that began June 16, and release their first album in eight years, "Music From Another Dimension," on November 6.

The flamboyant rocker's departure leaves a big hole on the "American Idol" judges panel as he has been a fan favorite. He helped create one of this past season's dramatic moments when young Jessica Sanchez was voted off by fans, then saved from elimination after Tyler and fellow judge Jackson stormed the stage in her defense. Sanchez went on to the finals.

Still in doubt is the fate of Lopez, another music superstar, who just this morning on NBC's "Today" show seemed still undecided about her next move.

"It's been on my mind a lot, as you can imagine," she said. "You know, I signed on to 'American Idol' to do one year, and ... I wound up doing the two years. And now it's like, 'OK, do we continue on this journey?'"

(Additional reporting by Courtney Garcia; Editing by Jan Paschal)

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