E! confirmed the news in a statement:
Kelly Osbourne is departing E!s "Fashion Police" to pursue other opportunities, and we would like to thank her for her many contributions to the series over the past five years, during which time the show became a hit with viewers. "Fashion Police" will return, as scheduled, on Friday, March 30th at 9:00 p.m. and no decisions have been made on her replacement.
The announcement comes four days after Osbourne's "Fashion Police" co-star Giuliana Rancic drew on stereotypes about locs and the people (usually of color) who have them to joke that Zendaya's hair on the Oscars red carpet probably smelled like "patchouli oil" and "weed." The next day, Kelly tweeted that she was "seriously questioning staying on the show" amid public outcry.
While it's tempting to connect the incidents, neither party has confirmed the exact reason for Osbourne's departure.
But perhaps the alleged tension dates back even further -- in 2013, Osbourne told the crowd assembled at a Lucky magazine conference that she was contractually obligated to maintain her signature lavender hair color, despite repeated requests to change it.