On the recordApril 26, 2001
Apart from the steps the President has to take if he is going to obtain this national security waiver, so that the item would be controlled, how long does that order last? And isn't there a limitation so that he can only issue that three times, for 6 months at a time, after which the President no longer has any control? In other words, the longest period of time he can control an item is 18 months. And after that, even the President has no authority.
Source
govinfo.gov




