Diane Sawyer will be leaving ABC's "World News."

According to Variety, Diane Sawyer will step down as lead anchor on ABC's "World News" and take on enterprise projects.  Sawyer's anchor duties will be split by George Stephanopoulos and David Muir. They will take on the lead anchor responsibilities for all special reports and breaking news.

Beginning on September 2, they will ascend to anchor and managing editor of "World News." Splitting the anchoring duties is unorthodox for network news. Usually the networks use a single anchor to deliver the top news. Muir will continue to anchor primetime newsmagazine "20/20″ with Elizabeth Vargas.

Former ABC News chief Ben Sherwood sent a memo to staffer saying the move comes because Sawyer wants to get away from covering daily headlines and focus more of her time on original reporting. Ben Sherwood will be taking on the role of overseer of Disney's non-sports TV assets.

In a statement from said ABC News President James Goldston, we learned that Sawyer approached Sherwood at the end of 2013.

Goldston said Muir, "will play a key role in covering the biggest breaking news events as they happen." Goldston said Stephanopoulos will lead ABC News' election coverage, starting in the fall when he will cover mid-term elections.

Muir was expected to be named the eventual successor to Diane Sawyer on "World News." In the past few months he has anchored many breaking-news special reports.

Former White House press secretary George Stephanopoulos one of the lead anchors of "Good Morning America," and also hosts "This Week," ABC's Sunday public-affairs program.