The Department of Justice is suing to block AT&T's purchase of Time Warner, legally challenging a $85 billion deal that would give the telecom giant control of a media empire including CNN, Warner Brothers, HBO, and other major media brands.
"This merger would significantly hurt American purchasers", Mr. Delrahim, the associate lawyer general for antitrust, said in an announcement.
AT&T, which sees the deal as a way to compete against emerging technology companies such as Netflix Inc and Amazon.com Inc's Prime Video, described the lawsuit as "a radical and inexplicable departure from decades of antitrust precedent".
This follows a period filled with reports that the DOJ demanded AT&T and Time Warner sell Turner Broadcasting, which includes CNN.
AT&T reaffirmed its plans to challenge the government's lawsuit, arguing that its plan is a "vertical" merger without competitive overlap.
By testing the arrangement, the Justice Department is adopting a starkly unique strategy to antitrust issues than the Obama organization did. A similar Comcast/NBC Universal merger in 2011 went through with some conditions attached.
"Blocking this merger is the right thing to do - and we hope the Justice Department is doing it for the right reasons", said Craig Aaron, president of advocacy group Free Press, which opposes media industry consolidation.
AT&T's rocky quest to complete its acquisition of Time Warner just hit another speed bump.
AT&T CEO Randall Stephenson said the idea his company would be too powerful after the deal "borders on the comical".
"We are confident that the court will reject the government's claims and permit this merger under longstanding legal precedent", McAtee said.