Stephanopoulos to anchor 'GMA'

Official announcement expected Thursday

NEW YORK -- ABC News plans to announce on Thursday that George Stephanopoulos will become an anchor of "Good Morning America" in a long-expected change that sees Diane Sawyer step up to head the TV network's nightly news.

Stephanopoulos, 48, is a former political adviser to the administration of President Bill Clinton. After leaving the White House, he took roles co-hosting ABC News coverage of political events and appeared regularly on ABC News shows.

He is expected to keep his Sunday news program "This Week" "for the foreseeable future," an ABC spokesman said on Wednesday. He begins his role on news and talk show "Good Morning America" (GMA) on December 14.

Robin Roberts will remain co-anchor at GMA, which is the second most-watched morning news program in the United States behind NBC's "Today." The GMA spokesman declined further comment on any other line-up changes.

Media reports have said Chris Cuomo, GMA's news reader, is leaving GMA and will be replaced by JuJu Chang.

Sawyer begins solo anchor duties at "World News" on December 21, replacing Charles Gibson, who in September said he would step down. She joins Katie Couric of the "CBS Evening News" as a female anchor of a major U.S. broadcaster's nightly news.