The Biden administration has banned approvals of new telecommunications equipment from China’s Huawei Technologies and ZTE because they pose “an unacceptable risk” to U.S. national security.

The Guardian reports that the U.S. Federal Communications Commission (FCC) said on November 25 it had adopted the final rules, which also bar the sale or import of equipment made by Chinese surveillance equipment maker Dahua Technology, video surveillance firm Hangzhou Hikvision Digital Technology and telecoms firm Hytera Communications Corp.

The move represents Washington’s latest crackdown on the Chinese tech giants amid fears that Beijing could use them to spy on Americans.

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“These new rules are an important part of our ongoing actions to protect the American people from national security threats involving telecommunications,” the FCC chairwoman, Jessica Rosenworcel, said in a statement.

Huawei declined to comment. ZTE, Dahua, Hytera and the Chinese embassy in Washington did not immediately respond to requests for comment.