President Donald Trump has declared a national emergency to protect American data networks from "foreign opponents".
The president wrote an executive order that effectively prevents US companies from using foreign telecoms which are believed to pose a security risk to the country.
Mr. Trump does not name any company specifically in the order.
But analysts suggest that it is mainly addressed to the Chinese telecommunications giant Huawei.
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According to a statement from the White House, Trump's orders strive to "protect America from foreign opponents who actively and increasingly create and exploit vulnerabilities in infrastructure and information and communications technology services."
It gives the commercial secretary the power to "prohibit transactions that constitute an unacceptable risk to national security", the statement adds.
The ship was immediately welcomed by the Federal Communications Commission, President Ajit Pai, who said in a statement that it was "an important step towards securing America's network".
The United States had already restricted the federal authorities from using Huawei products and has urged allies to eliminate them, while Australia and New Zealand have both blocked the use of Huawei tools in the next-generation 5G mobile network.
But Huawei – which is the world's largest manufacturer of telecom equipment – has strongly denied claims.
Meanwhile, his chairman Liang Hua said it was "willing to sign non-spy agreements with governments" during a meeting in London on Tuesday, which is over the security of their products used in the next-generation 5G mobile network continued to grow.
Trump's latest move is likely to increase relations with China, which is already burdened when the two participate in a trade war.
The United States more than doubled to 200 billion kronor (154.9 billion pounds) on Chinese goods on Friday and China was recalled with its own charges on US products.
This escalated the situation that only recently seemed to approach a ruling n.