United States President Donald Trump on Wednesday signed an executive order declaring a national emergency to effectively bar American telecom companies from using foreign-made equipment believed to pose threats to national security, BBC reported.

The order does not name a country or companies, but it appears to target Chinese telecom giant Huawei, which is the world’s biggest supplier of network gear used by phone and internet companies, according to AP. Several countries, including the US, have raised concerns that Huawei products could be used by China for surveillance, but the company has denied the allegations.

Commerce Secretary Wilbur Ross said the order, which has been under review for more than a year, is aimed at protecting the supply chain from “foreign adversaries to the nation’s information and communications technology and services supply chain”, reported The Guardian. “Under President Trump’s leadership, Americans will be able to trust that our data and infrastructure are secure.”

In a separate move, the US commerce department added Huawei to its “entity list” to ban the company from acquiring technology from US firms without government approval. This will make it harder for Huawei to do business with US companies.

Huawei said restricting it from doing business in the US “will not make the US more secure or stronger”. “...instead, this will only serve to limit the US to inferior yet more expensive alternatives, leaving the US lagging behind in 5G deployment, and eventually harming the interests of US companies and consumers,” it said in a statement, according to CNBC. “We are ready and willing to engage with the US government and come up with effective measures to ensure product security.”

The move comes amid a trade war between the two countries. Talks between Washington and Beijing have come to a halt. On May 10, Trump increased import duty on most Chinese goods, worth a total of about $300 billion. Earlier this week, Beijing announced plans to increase tariffs on $60 billion worth of US imports beginning on June 1.