President Donald Trump isn’t done ratcheting up pressure on the Chinese government. Amid a widening trade war that’s gone tit-for-tat the past few days, Trump today signed an executive order that invokes national emergency powers to “deal with the threat posed” by IT and communications technology or services owned or otherwise controlled by foreign adversaries.

China is not implicitly named in the 545-word executive order, but the action is clearly directed at Chinese-based vendors Huawei and ZTE. Indeed, rumors have been circling for months that such an order was imminent.

“Foreign adversaries are increasingly creating and exploiting vulnerabilities in information and communications technology and services, which store and communicate vast amounts of sensitive information, facilitate the digital economy, and support critical infrastructure and vital emergency services, in order to commit malicious cyber-enabled actions, including economic and industrial espionage against the United States and its people,” Trump wrote in the order.

The latest spat comes as Huawei wages war on multiple fronts, including allegations of espionage, intellectual property theft, security vulnerabilities in its software, and the detention of its CFO Wanzhou Meng (at the request of the U.S. government).

Huawei denies all wrongdoing and filed a lawsuit against the U.S. government in March to challenge a less comprehensive ban on its equipment. The company has never been caught in an act of espionage, and U.S. officials have never publicly provided proof to support its claims.

“Protecting America’s communications networks is vital to our national, economic, and personal security. I therefore applaud the president for issuing this executive order to safeguard the communications supply chain,” FCC Chairman Ajit Pai wrote in a prepared statement. “Given the threats presented by certain foreign companies’ equipment and services, this is a significant step toward securing America’s networks.”

Potential impacts and actions taken as a result of the order are being delegated to Trump’s cabinet including securities of commerce, treasury, defense, and homeland security, the attorney general, FCC Chairman Ajit Pai, and the director of national intelligence.

“Although maintaining an open investment climate in information and communications technology, and in the United States economy more generally, is important for the overall growth and prosperity of the United States, such openness must be balanced by the need to protect our country against critical national security threats,” Trump wrote.

Prohibitive actions will be triggered when a transaction “poses an undue risk of sabotage to or subversion of the design, integrity, manufacturing, production, distribution, installation, operation, or maintenance of information and communications technology or services in the United States,” according to the order.

“President Trump’s decision sends a clear message that the United States will do what it takes to secure our communications networks,” FCC Commissioner Brendan Carr wrote in a prepared statement. “The executive order will ensure that our foreign adversaries do not compromise the security of our networks or undermine our core values, including our freedom from unlawful surveillance and respect for intellectual property.”

Transactions can also be blocked if the cabinet determines that a company “poses an undue risk of catastrophic effects on the security or resiliency” of critical U.S. infrastructure or “otherwise poses an unacceptable risk” to U.S. national security.

“When it comes to our national security, we cannot afford to make risky choices and just hope for the best,” Pai wrote. “We must have a clear-eyed view of the threats that we face and be prepared to do what is necessary to counter those threats.”