The two companies have been dancing around a possible merger for years, and were again in the news in recent weeks with talks of coming together after all.
Claure said Sprint has agreed it is best to move forward on its own with "significant assets, including our rich spectrum holdings, and are accelerating significant investments in our network to ensure our continued growth".
Sprint parent company Softbank is reportedly chatting up Charter Communications about a possible merger, amid indications that Sprint's merger deal with T-Mobile US has tanked.
T-Mobile is owned by Deutsche Telekom, and Sprint is owned by SoftBank.
Wireless carriers Sprint and T-Mobile called off a potential merger, saying the companies couldn't come to an agreement that would benefit customers and shareholders.
Sources claim T-Mobile CEO John Legere reached out to Sprint's CEO Marcelo Claure following a T-Mobile board meeting held to decide whether the carrier would attempt to revive the deal. But T-Mobile won't pursue a deal that doesn't "result in superior long-term value for T-Mobile's shareholders compared to our outstanding stand-alone performance and track record", he said.
Both companies had expressed interest in a tie-up this year, and industry analysts expected T-Mobile to have more leverage in discussions this time around.
It comes as Sprint has somewhat struggled in an increasingly competitive USA mobile market.
Although it has cut its costs, Sprint is saddled with considerable debt and has endured numerous annual losses.
In December, SoftBank CEO Masayoshi Son met at Trump Tower with then-President-elect Donald Trump, rekindling speculation that SoftBank would renew merger efforts under a Republican administration.