In a brief joint statement Saturday, the companies said they were "unable to find mutually agreeable terms."
The move wasn't a surprise. A Mondayby Japanese publication Nikkei said Sprint's parent company, Japan-based carrier SoftBank, planned to break off merger talks because of a dispute over ownership of the combined company.
The report said SoftBank and's parent company, German carrier Deutsche Telekom, had reached a broad agreement but hadn't settled on who would control the merged entity. Deutsche Telekom reportedly had insisted on a controlling stake, something SoftBank initially was open to but then reconsidered, Nikkei said. Deutsche Telekom declined to comment on that report, and SoftBank didn't respond to a request for comment.
On Sunday, Softbank said it plans to increase its ownership stake in Sprint.
""We are entering an era where billions of new connected devices and sensors will come online throughout the United States," Softbank CEO Masayoshi Son said in a statement. "Continuing to own a world class mobile network is central to our vision of ubiquitous connectivity."
A possible merger between T-Mobile and Sprint had been rumored for years. The two companies lag behind their bigger rivals, Verizon Wireless and AT&T, when it comes to the US market. Combining would give them an advantage, but critics fear having three players would reduce competition and hurt consumers.
Sprint and T-Mobile both said Saturday that they had no additional comment to make about the end of the merger talks.
On Sunday, Sprint announced a mobile networking agreement with broadband provider Altice USA
CNET's Shara Tibken contributed to this report.
Originally published Nov. 4 at 11:53 a.m. PT.
Update Nov. 5 at 3:38 p.m. PT: Added information on Softbank's investment in Sprint and on Sprint's deal with Altice.
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