Christina Norman has left her position as chief executive officer of OWN, the cable network owned by Oprah Winfrey and Discovery Communications. Effective immediately, Peter Liguori, currently COO of Discovery Communications, will serve as the interim CEO.

The network has been struggling since its launch in January 2011.

"Given all that we have to do, the OWN board felt it was necessary that we have a different kind of leadership in place for the next phase of OWN's growth," according to a Winfrey memo that was obtained by Reuters.

The company said in a press release that Liguori's appointment reflects a transition from a launch phase to a more long-term focus on business and creative strategy, development and execution following the network's debut on January 1, 2011.

“I want to thank Christina for her important accomplishments, incredible passion and many sacrifices in helping to launch the network,” Winfrey said in a statement. "With the final taping of The Oprah Winfrey Show only a few weeks away, I will soon be able to devote my full energies to OWN. This is a natural point of transition, and I am confident that Peter, as an integral part of the launch of OWN, will be a terrific partner for me going forward."

Prior to joining OWN in 2009, Norman served as president of MTV where she oversaw strategy and management for the networks many channels. She also served as president of Viacom’s VH1.

In addition to his current position, Liguori will oversee the network's new content, including the October debut of Rosie O'Donnell's new talk show and the launch of Oprah's Next Chapter in 2012.

(Photo: Frederick M. Brown/Getty Images)