FedEx Corporation sued the US Department of Commerce Monday for what they say is the Department’s efforts to use their regulations to “essentially deputize FedEx to police the contents of the millions of packages it ships daily even though doing so is a virtually impossible task, logistically, economically, and in many cases, legally.”

In an interview, FedEx CEO Fred Smith said that “they cannot be the policeman for the Department of Commerce.” He also said that the regulations place an enormous burden on FedEx and other common carriers to know exactly what is in each package and from whom it originates. FedEx ships more than 15 million packages daily, and he said it would be impossible to police every package.

The suit stems from controversy regarding FedEx’s handling of a package from Huawei, which is on the Department of Commerce’s Entity list after President Donald Trump signed an Executive Order that prevents US companies from doing business with the Chinese tech giant, among others.