A bipartisan group of senators wants President Trump’s administration to suspend its approval of U.S. technology sales to China’s Huawei, saying the manufacturer of cellphones and 5G network equipment poses risks to national security.

In a letter to Trump sent Thursday, 15 senators expressed concern about the Commerce Department’s move to begin issuing licenses allowing some sales of semiconductors and other parts, despite Huawei’s remaining on a U.S. trade blacklist. The Commerce Department’s action was announced Wednesday.

The senators, led by Minority Leader Charles E. Schumer (D-N.Y.) and Tom Cotton (R-Ark.), asked the president to suspend the granting of licenses until the Commerce Department briefs Congress on the national security implications.

“You have said yourself that you did not want the U.S. doing business with Huawei,” the senators wrote. “National security experts widely agree that Chinese companies cooperate heavily with the Chinese Communist Party, and the Chinese government is thought to exercise considerable influence over Huawei, in particular.”

Asked for comment on the senators’ letter, the Commerce Department said it was granting licenses after an interagency review only for “limited and specific activities which do not pose a significant risk to the national security or foreign policy interests of the United States.”

The United States banned U.S. tech sales to Huawei in May after calling it a security threat, saying the Chinese government could tap into Huawei telecom network gear installed abroad to spy on the West or disrupt infrastructure. Adding Huawei to the trade blacklist was part of a broad U.S. push against the Chinese company, which the United States also accuses of violating U.S. sanctions on Iran.

Huawei has denied U.S. allegations that it is a security risk or subject to interference by China’s ruling Communist Party. Schumer and Cotton recently have raised other concerns about China. In October, they asked U.S. intelligence officials to determine whether the Chinese-owned social-networking app TikTok poses national security risks.

After the Huawei trade ban, dozens of tech suppliers that previously sold billions of dollars of semiconductors and software to Huawei each year applied for special licenses to resume some sales.

The licenses the Commerce Department is approving relate to Huawei consumer products deemed to pose no potential security threats, according to a tech-industry official who spoke on the condition of anonymity to discuss nonpublic information. That likely includes chips and other parts used in Huawei cellphones or laptops.

The Commerce Department is denying license requests to sell parts Huawei uses to build equipment for wireless phone and Internet networks, including super-fast 5G networks, the industry official said.

The Commerce Department approved roughly one-quarter of the nearly 300 license applications it received and is notifying companies of its intent to deny another one-quarter of those applications, according to the industry official. The Commerce Department declined to comment on which, or how many, licenses it approved.

President Trump has suggested he could ease up on Huawei as part of a larger trade deal. Trade talks with China appear to be languishing, with the president on Wednesday accusing Beijing of foot-dragging. China has said relief for Huawei is essential if Beijing is to agree to any trade deal.