John Kennedy actually said...
I determine that the modifications of existing duties and other import restrictions of the United States, the additional import restrictions, and the continuance of existing customs and excise treatment of articles imported into the United States proclaimed in part III of this proclamation will be required or appropriate to carry out the trade agreement identified in paragraph (1) of this part.
Context
Proclamation 3512—Trade Agreement Supplementary to the General Agreement on Tariffs and Trade Containing Concessions...
12/27/1962