AT&T has reportedly backed off from a proposal to sell Chinese smartphone manufacturer Huawei’s devices in the U.S. at the last minute on Monday.

It wasn’t immediately clear why AT&T bounced on its deal with the Shenzen, China-based manufacturer just one day before it was expected to announce the U.S. partnership at the Consumer Electronics Show in Las Vegas on Tuesday. AT&T remained tight-lipped to the Journal and all Huawei would comment is that it has “proven itself by delivering premium devices with integrity globally and in the U.S. market.” Huawei devices are available in the U.S. at some retail stores and online.

The National Security Agency’s ability to spy on vast quantities of Internet traffic passing through the United States has relied on its extraordinary, decades-long partnership with a single company: the telecom giant AT&T.

While it has been long known that American telecommunications companies worked closely with the spy agency, newly disclosed NSA documents show that the relationship with AT&T has been considered unique and especially productive. One document described it as “highly collaborative,” while another lauded the company’s “extreme willingness to help.