Former NBC chief Zucker to head CNN

Zucker will start in January as head of the 23 news and information businesses including the CNN news channel, CNN International and CNN.com, parent company Time Warner said in a statement.

Former CNN Worldwide president Jim Walton announced his departure in July, saying the struggling network needed "new thinking" after his 10 years at the helm.

The announcement came after CNN's viewer ratings hit their lowest levels in two decades, behind Fox News Channel and MSNBC.

Zucker stepped down as head of NBC Universal after the merger of the media and entertainment giant with cable television operator Comcast was completed in 2011.

"Jeff's experience as a news executive is unmatched for its breadth and success," said Phil Kent, head of CNN parent Turner Broadcasting.

"He built and sustained the number one brand in morning news, and under his watch, NBC's signature news programming set a standard for quality and professionalism. As a programmer, a brand-builder and a leader, he will bring energy and new thinking to CNN. I couldn't be happier to welcome him or more excited about what he'll accomplish here."

Zucker said: "I am thrilled to join the distinguished team of journalists across the worldwide platforms of CNN. The global reach and scale of the CNN brand is unparalleled in all of news. Outside of my family and the Miami Dolphins, there is nothing I am as passionate about as journalism... I'm excited to return to daily newsgathering and compelling storytelling in a place that values those above all else."

CNN was the first 24-hour news network, and reaches 100 million households in the United States and 265 million households abroad. It also has significant online and mobile reach and a global newsgathering network with 45 bureaus.

Zucker started his 25-year career with NBC as a researcher for NBC Sports' coverage of the 1988 Summer Olympic Games.

He was named executive producer of Today, a morning show, in January 1992 and then went on to be executive producer of NBC Nightly News and oversaw the network's coverage of the Gulf War, the 1993 and 1997 presidential inaugurations and the 2000 elections.

He was later promoted to president of NBC Entertainment, president of the NBC Entertainment, News & Cable group and president and CEO of the NBC Universal Television Group. Currently, Zucker is executive producer of the syndicated daytime show Katie.