U.S. intelligence officials told lawmakers this week that Americans should not use products made by Chinese tech giants Huawei or ZTE due to potential security concerns.

During their testimony before the Senate Intelligence Committee, CNN reports that U.S. Sen. Tom Cotton, R-Ark., asked whether leaders from the CIA, FBI, NSA and Defense Intelligence Agency would recommend using products or services from those companies — and that none raised their hands in response.

Consumers can currently purchase phones made by Huawei and ZTE in the U.S., but both companies are hindered due to a lack of an agreement with a major wireless carrier.

Huawei, in particular, sought to change that of late, but U.S. government pressure reportedly led AT&T and Verizon to walk away from the company.

A congressional report highlighted Huawei and ZTE as potential security risks due to their ties to the Chinese government as early as 2012. FBI Director Chris Wray elaborated Tuesday by mentioning the inherent risk of allowing companies “beholden to foreign governments” to access U.S. telecommunications.

“It provides the capacity to maliciously modify or steal information,” Wray told the committee, according to CNN. “And it provides the capacity to conduct undetected espionage.”

ZTE told the network that the publicly traded company was “committed to adhering to all applicable laws and regulations of the United States, work with carriers to pass strict testing protocols, and adhere to the highest business standards.”

Huawei, which defended its security record in recent months, largely declined to comment on the Senate committee hearing but said it was “monitoring developments” in Congress.