Ali Larijani, Speaker of the Iranian Majlis, said in an April 7, 2019 interview on Al-Jazeera network (Qatar) that he does not think the U.S. has lost its mind to the extent that it would add the IRGC to its list of terrorist organizations, and that if this were to happen, Iran would in turn consider the U.S. military and the Pentagon to be terrorist organizations, as well. The interviewer asked Larijani if this would mean that Iran would attack the U.S. military in Iraq or in situations where it is close to Iranian forces, but Larijani answered that there is no need to elaborate further on the matter and that the meaning is sufficiently clear. The interview was held before the U.S. declared it was adding the IRGC to its list of terrorist organizations.
Following are excerpts:
Interviewer: There are reports that the U.S. may include the IRGC on its list of terrorist organizations. Will there be an Iranian response if this happens?
Ali Larijani: I don't think that the U.S. has lost its mind to that extent. It is true that Trump does unusual things, but he is still somewhat reasonable. If the U.S. takes such a step, it would mean that the U.S. military would [also] be considered a terrorist force. The U.S. must take this into consideration.
Interviewer: How so?
Ali Larijani: The matter depends on the circumstances in the United States. If the U.S. takes such a measure, it would mean that the U.S. military and the Pentagon would, similarly, be considered terrorist groups.
[…]
Interviewer: How will you deal with it in practical terms? For example, will the U.S. forces in Iraq be attacked? Will the U.S. military be attacked wherever it is close to the Iranian forces?
Ali Larijani: We do not see a reason to elaborate further on this matter, although the general meaning of this is clear.