The executive order bans the use of equipment for the power grid that was manufactured by a company under the control of a foreign adversary, or the buying of any equipment that poses a national security threat.

“Additional steps are required to protect the security, integrity, and reliability of bulk-power system electric equipment used in the United States,” Trump wrote. “In light of these findings, I hereby declare a national emergency with respect to the threat to the United States bulk-power system.”