Pedestrians walk past a T-Mobile store in New York on Friday. (Lucas Jackson/Reuters)

T-Mobile and Sprint are reportedly nearing a merger deal that would combine the nation’s third- and fourth-largest wireless carriers, respectively — adding to a whirlwind of consolidation in the communications industry.

The proposed merger, first reported by Reuters, would give the resulting company control of roughly 100 million customers' accounts in the US, edging out AT&T’s 93 million and putting it within striking distance of Verizon’s roughly 116 million wireless customers. And it would reduce the number of national wireless operators from four to three at a time when Washington officials have voiced greater concern about corporate concentration.

Sprint and T-Mobile declined to comment.

T-Mobile has competed aggressively with its much larger rivals, peeling away customers with industry-changing business practices such as the elimination of long-term contracts. But analysts say T-Mobile needs to get bigger if it wants to be competitive in a world of next-generation 5G data, which will cost billions to deploy.

The combined company could spread out its costs and get the additional funding it needs to keep upgrading its network. But the merger would require convincing antitrust regulators that a deal that eliminates a competitor is good for consumers.

Thus far, the government has been skeptical. In 2011, AT&T dropped an attempted merger with T-Mobile after running into resistance from the Justice Department and the Federal Communications Commission. Three years later, Sprint called off merger negotiations with T-Mobile over the same concerns.

Despite the change in administration since then, many staffers at the two agencies remain the same, said Blair Levin, a former FCC official who now advises Wall Street on telecom issues. Still, he said, the Justice Department’s antitrust chief, Makan Delrahim, and FCC Chairman Ajit Pai, could be convinced.

“I do think it’s possible that both Ajit and Makan come to believe that they should allow the deal,” Levin said.

To bolster their case before regulators, T-Mobile and Sprint are also expected to argue that competition is rising — from the cable industry.

Cable companies such as Comcast and Charter Communications have leaped into the wireless sector with fledgling cellular carriers of their own. Unlike pure cellular networks like T-Mobile’s, these services mix wireless service from traditional providers such as Verizon with the cable companies’ existing WiFi hotspots.

Comcast’s Xfinity Mobile has 577,000 customers so far after launching last year, Comcast executives said this week on an earnings call.

It is unclear whether regulators will agree that the cable industry represents a credible threat to the traditional wireless industry.

Another wild card may be Sprint's and T-Mobile’s foreign ownership. In 2013, the Japanese conglomerate Softbank invested $21.6 billion for a 72 percent stake in Sprint. Its chief executive, Masayoshi Son, has since increased Softbank’s stake to roughly 85 percent. Meanwhile, T-Mobile’s parent is the German firm Deutsche Telekom.

The White House has frequently weighed in on proposed mergers, particularly those involving foreign companies. Broadcom — a chip manufacturer that was based in Singapore until this month, when it relocated to Delaware — was forced to abandon its takeover of the U.S.-based chipmaker Qualcomm, over concerns that it could give China an edge in the development of 5G networks.

President Trump has also opined on other companies in the telecom and media industries that are seeking deals. He famously attacked AT&T’s proposed purchase of Time Warner during the 2016 campaign, for example, citing the deal as an example of too much power “in the hands of too few.”

The Justice Department is wrapping up its trial to block that $85 billion merger, and a court decision is expected in the coming weeks.

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