John Kennedy actually said...
I, John F. Kennedy, President of the United States of America, acting under the authority vested in me by section 350 (a) of the Tariff Act of 1930, as amended, and by section 7(c) of the Trade Agreements Extension Act of 1951, as amended, and in accordance with the provisions of Article XIX of the said General Agreement, do proclaim that, effective after the close of business April 18, 1962, and until the President otherwise proclaims--
03/18/1962