AT&T walked away from a smartphone partnership with Chinese electronics giant Huawei due to pressure from U.S. lawmakers, according to a new report.

Sources told Reuters that members of Congress had urged federal regulators to oppose the deal, and that they continue to pressure AT&T to all cut ties to Huawei, including the sale of handsets by the company’s prepaid brand Cricket Wireless and their cooperation on a global initiative to develop 5G standards.

“The next wave of wireless communication has enormous economic and national security implications," Michael Wessel of the U.S.-China Economic and Security Review Commission told Reuters. "China’s participation in setting the standards and selling the equipment raises many national security issues that demand strict and prompt attention."

Two unnamed congressional aides told the news service that lawmakers were concerned about security issues — namely, that Huawei's ties to the Chinese government could allow Beijing to collect data from its U.S. users.

One aide also signaled that maintaining ties could make it more difficult for U.S. companies to do business with Washington.

Huawei was slated to announce the deal with AT&T — its first with a U.S. carrier — at CES in an effort to gain a foothold in the U.S. market this year. AT&T, however, backed out of the deal at the last minute, and reports last week noted that Huawei was identified as a potential national security concern in a 2012 congressional report.

The Chinese tech giant again defended its security standards as "a lot better than the other vendors" in recent weeks.

The aides also told Reuters that lawmakers are opposed to a seven-year-old application from wireless carrier China Mobile to begin operating in the U.S. That filing remains pending before the Federal Communications Commission.