The Department of Justice (DOJ) filed a lawsuit today to prevent AT&T from acquiring T-Mobile. AT&T is the largest provider of mobile and fixed phone services in the U.S., and T-Mobile is among the top mobile phone service providers in the world.

The DOJ said in a press release today that “the proposed $39 billion transaction would substantially lessen competition for mobile wireless telecommunications services across the United States, resulting in higher prices, poorer quality services, fewer choices and fewer innovative products for the millions of American consumers who rely on mobile wireless services in their everyday lives.”

At time of publication of this article, neither company has yet to release statements on the DOJ's decision to sue.

List to NPR's Morning Edition report on the story.