Charles Gibson leaving 'World News'

Diane Sawyer will take over as anchor in Jan.

NEW YORK -- Charles Gibson is leaving his post as anchor of ABC News' "World News" at the end of the year and will retire from full-time work.

"Good Morning America" anchor Diane Sawyer will take over the "World News" anchor seat, which Gibson has occupied since May 2006, beginning in January.

"It has not been an easy decision to make," Gibson said in an e-mail to the "World News" staff. "This has been my professional home for almost 35 years. And I love this news department, and all who work in it, to the depths of my soul."

ABC News president David Westin said that he and Gibson have been talking about the decision for several weeks and that Gibson "has persuaded me that this is both what he wants and what is best for him."

Gibson, 66, said he had been planning to retire at the end of 2007 but events compelled him to stay. He was named anchor following the death of Peter Jennings and the wartime injury of Bob Woodruff in 2006.

Gibson plans to continue as an occasional contributor.

Sawyer's elevation means that, with Katie Couric at CBS, two of the three leading anchors for the broadcast networks will be women.

Sawyer's departure leaves a hole at "GMA," where she was the show's centerpiece and co-host with Robin Roberts. ABC had no immediate announcement on what will happen on that show, though in-house candidates Bill Weir and Chris Cuomo would be prospects to take a larger role.

The Associated Press contributed to this report.