FILE PHOTO: Lachlan Murdoch, son of Rupert Murdoch, 21st Century Fox CEO, arrives at the annual Allen and Co. conference at the Sun Valley, Idaho Resort July 11, 2013. REUTERS/Rick Wilking/File Photo

(Reuters) - Twenty-First Century Fox would never be interested in buying CNN, Fox Executive Chair Lachlan Murdoch said on Wednesday at a conference organized by the news website Business Insider in New York.

Last week, the U.S. Department of Justice filed suit to block AT&T's planned $85.4 billion acquisition of Time Warner Inc TWX.N, the parent of CNN, because of antitrust concerns about the merged company owning too much content and distribution.

Before the suit, Justice Department staff had recommended AT&T sell either its DirecTV unit or Time Warner’s Turner Broadcasting unit, which includes CNN, to win antitrust approval, sources have told Reuters.

Earlier this month, Reuters first reported that Rupert Murdoch, who shares the title of executive chair of Fox, telephoned AT&T CEO Randall Stephenson twice to discuss CNN during the past six months.

“We wouldn’t be allowed to buy CNN and we would never be interested in buying CNN,” Lachlan Murdoch, Rupert’s oldest son, said at the Business Insider conference.

Fox owns Fox News and while there is no law against a company owning two cable networks, a deal could raise antitrust concerns.

Stephenson has said he has no intention of selling CNN to gain approval of the acquisition of Time Warner.

Lachlan Murdoch declined to comment on reports that Fox has been approached by a number of suitors, including Walt Disney Co, for a sizeable piece of its business, adding that he feels strongly about the company’s standing as a standalone company.

He did acknowledge the challenges facing media companies today, noting as the pace of cable subscribers declines in the United States increased, international revenue and having a direct to consumer offering is increasingly important.