No proclamation shall be made pursuant to the provisions of this chapter reducing or eliminating the duty or other import restriction on any article if the President determines that such reduction or elimination would threaten to impair the national security.

While there is in effect with respect to any article any action taken under section 2253 of this title, or section 1862 or 1981 of this title, the President shall reserve such article from negotiations under this subchapter (and from any action under section 2132(c) of this title) contemplating reduction or elimination of—

(Pub. L. 93–618, title I, § 127(a), (b), Jan. 3, 1975, 88 Stat. 1993.)