No defense article or defense service may be sold or licensed for export under this chapter in a fiscal year to a foreign country that the President determines and certifies to Congress, by May 15 of the calendar year in which that fiscal year begins, is not cooperating fully with United States antiterrorism efforts.

The President may waive the prohibition set forth in subsection (a) with respect to a specific transaction if the President determines that the transaction is important to the national interests of the United States.