CHICAGO -- Oprah Winfrey's iconic television talk show will end in 2011 after 25 seasons on the air, Harpo Productions said Thursday.

It was not clear why she made the decision to take the show off the air, CBS station WBBM reports.

Winfrey plans to give more details live for "The Oprah Winfrey Show" on a live Friday broadcast, according to Chicago-based Harpo Productions Inc. (Oprah airs on KSNT in Topeka at 4:00pm.)

The show will draw to a close on September 9, 2011, according to a statement by Tim Bennett, president of Harpo, Inc.

"Oprah’s personal comments about this on tomorrow’s live show will mark an historic television moment that we will all be talking about for years to come," Bennett said.

Winfrey started her broadcasting career in Nashville, Tennessee and Baltimore, Maryland, before relocating to Chicago in 1984 to host WLS-TV's morning talk show "A.M. Chicago." That show was renamed "The Oprah Winfrey Show" in 1985.

A year later, Winfrey established Harpo and her talk show went into syndication. In 1990, Winfrey opened Harpo Studios in Chicago's West Loop neighborhood.

Over the years, Winfrey drew Chicago into her spotlight. In September, she drew more than 20,000 fans to a taping of her show on Michigan Avenue. A tearful Winfrey was in Chicago's Grant Park as Barack Obama was elected president.

She also lobbied for Chicago's failed bid to host the 2016 Olympics, traveling to Denmark in an attempt to woo members of the International Olympic Committee to vote for her hometown.

In January 2008, Winfrey opened The Oprah Store - a 5,500-square-foot hybrid souvenir shop and trendy boutique - near her studios in an area that was once a warehouse district. It has hosted an average 250 post-Oprah show shoppers and curious Winfrey fans a day.