After months of on-again-off-again discussions about merging, T-Mobile and Sprint have officially called it quits. The companies jointly announced today that they have ended negotiations after they were “unable to find mutually agreeable terms.”

In its announcement, Sprint’s President and CEO Marcelo Claure says that while they recognized the potential value in merging, “we have agreed that it is best to move forward on our own.” T-Mobile’s President and CEO John Legere outlined that any merger would have to bring in long-term value to his shareholders.

There’s been widespread speculation for months that the two companies would merge to challenge their larger rivals, AT&T and Verizon. In May, Sprint and T-Mobile resumed preliminary and informal talks about a merger – a discussion which dates all the back to 2014 when Sprint began its pursuit to buy T-Mobile. The rumors renewed this September when both sides were reportedly close to reaching tentative terms. Those talks apparently collapsed last week as Sprint reportedly called them off, only to have T-Mobile make a revised offer, which Sprint has apparently rejected.

The companies have let open the possibility of other mergers, however: Claure noted that he believes that “significant opportunities exist to establish strong partnerships across multiple industries.” Earlier this summer, The Wall Street Journal reported that Sprint proposed a merger with Charter.