US lawmakers have long worried about the security risks posed the alleged ties between Chinese companies Huawei and ZTE and the country’s government. To that end, Texas Representative Mike Conaway introduced a bill last week called Defending U.S. Government Communications Act, which aims to ban US government agencies from using phones and equipment from the companies.

Conaway’s bill would prohibit the US government from purchasing and using “telecommunications equipment and/or services,” from Huawei and ZTE. In a statement on his site, he says that technology coming from the country poses a threat to national security, and that use of this equipment “would be inviting Chinese surveillance into all aspects of our lives,” and cites US Intelligence and counterintelligence officials who say that Huawei has shared information with state leaders, and that the its business in the US is growing, representing a further security risk.

The bill is another major headache for Huawei, which last week saw its partnership with AT&T abruptly collapse, prompting the company’s CEO to go off script during a CES presentation. Under the deal, the company would be able to sell its new flagship Mate 10 Pro phone in the US through AT&T. The partnership between the two companies attracted unwanted scrutiny by US lawmakers, who sent a letter with their concerns to the Federal Communications Commission in December, according to The New York Times.

Conaway’s bill is part of a larger trend of concerns over foreign-built software and hardware. Last summer, the heads of the six major US intelligence agencies told a Senate Intelligence Committee that they had concerns over using security products from Kaspersky Lab, while the UK’s national Cyber Security Centre issued a new guidance over the Russian-company’s products, citing concerns about potential connections to the Russian government.

Lawmakers have long worried about Huawei and ZTE date, and Conaway’s bill is a new chapter in that saga. In 2010, four senators contacted the FCC with concerns over the alleged ties between the companies and the Chinese government. In 2011, the two companies were the subject of a report from the House of Representative’s Permanent Select Committee on Intelligence, which recommended that the US government be prohibited from buying Huawei and ZTE products, as well as continued vigilance, investigation, and legislation to address the concerns. The US also isn’t the only country to worry about the companies: the Australian government upheld a prohibition in 2013 that barred Huawei from bidding on work on the country’s National Broadband Network. But the 2011 Congressional report doesn’t cite direct evidence that the company is compromised, instead saying that Huawei has failed to provide evidence that would “satisfy any fair and full investigation,” and Huawei has consistently denied allegations of collusion with the Chinese government.

In their book, Cybersecurity and Cyberwar: What Everyone Needs to Know, P.W. Singer and Allan Friedman argue that there is a growing cybersecurity risk as complicated hardware supply chains harbor plenty of opportunities for foreign agents to compromise equipment. Singer tells The Verge that there is also reason for the government to be wary of using foreign-built hardware, especially long-term. “If a potential adversary is making the systems and software that you use,” he says, “you don’t just have dependency, but also potential vulnerability that can be exploited not just now, but years into the future.”

While the potential for a cybersecurity concerns exists, Huawei and ZTE have long been targets for members of Congress, and this bill could be a form of political signaling to China. Conaway specifically cites President Donald Trump’s and his American First attitude, who has accused China of taking advantage of US interests, and says that the country is specifically trying to “compromise the integrity of U.S.businesses and spy on our closely held national security secrets.”