The actor plans to quit the NBC hospital drama after next season to pursue directing and producing opportunities, Variety and The Hollywood Reporter reported Monday.
His three-year, $27 million contract expires next May.
La Salle has been with the show since its 1994 debut and earned three Emmy nominations for his role as the brooding Dr. Peter Benton.
"We're sorry that Eriq won't continue on 'ER,' but we are thrilled he will be around for one more year," NBC Entertainment president Jeff Zucker said. "We thank him for his enormous contributions toward making the show America's top-rated drama for seven years."
La Salle is finishing "Crazy as Hell," his first feature film as a director. He also served as producer on the upcoming thriller "The Salton Sea."
"ER" will enter its 2002-03 season with Noah Wyle as the only original cast member remaining. Sherry Stringfield, another charter cast member, left in 1996 but is returning only for the upcoming fall season.
Anthony Edwards already announced he'll leave the show after this season.
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