It
does invoke laws passed by Congress, one which specifically grants powers to the President:
50 U.S. Code § 1702 - Presidential Authorities [0]:
(1) At the times and to the extent specified in section 1701 of this title, the President may, under such regulations as he may prescribe, by means of instructions, licenses, or otherwise—
(B) investigate, block during the pendency of an investigation, regulate, direct and compel, nullify, void, prevent or prohibit, any acquisition, holding, withholding, use, transfer, withdrawal, transportation, importation or exportation of, or dealing in, or exercising any right, power, or privilege with respect to, or transactions involving, any property in which any foreign country or a national thereof has any interest by any person, or with respect to any property, subject to the jurisdiction of the United States;
[0] https://www.law.cornell.edu/uscode/text/50/1702