Things were looking good for the T-Mobile U.S. Inc. and Sprint Corp. merger on Monday after Federal Communications Commission Chairman Ajit Pai gave it the green light. Then the Department of Justice weighed in and suddenly it didn’t look so good after all.

Pai said in a statement that he believed the merger would be in the public interest and he would be recommending approval. “This is a unique opportunity to speed up the deployment of 5G throughout the United States and bring much faster mobile broadband to rural Americans,” he said. “We should seize this opportunity.”

The two carriers assured the FCC that 97% of the U.S. population would have 5G access within three years of the deal closing, including 85% of rural Americans. After six years, that would increase to 99% overall and 90% of people living in rural areas.

T-Mobile Chief Executive John Legere said in a blog post that this commitment is not just bluster and indeed is “enforceable” and “verifiable.” He said the merger would “put the U.S. at the forefront of 5G innovation, driving massive economic growth, helping bridge the Digital Divide, creating more competition, and of course, giving consumers and businesses more for less.”

That said, the $26 billion deal would always need the approval of the Justice Department and reports earlier this year suggested that might not happen because it could undermine competition in the wireless industry.

That refusal still looks on the cards, with Bloomberg reporting not long after the Pai nod of approval that people familiar with the review have said the DOJ is still invoking antitrust issues as a reason to give the thumb down.

That report said that while the FCC and DOJ don’t usually disagree on a proposed merger, the antitrust concerns outweigh all the benefits the two companies are offering. As reported by Forbes, some digital rights groups have also said such a consolidation of power would be bad for competition and consequently harm consumers.

Image: Mike Mozart/Flickr