Transcript for Trump expected to 'decertify' Iran deal

The president is set to deliver a major speech today on the fate of America's nuclear deal with Iran. President trump has consistently called it terrible for the U.S. And our chief global affairs correspondent Martha Raddatz is in Washington with more. Martha, what can we expect here? Reporter: Well, robin, in fact president trump called it the worst deal ever but the president is not expected to walk away from the nuclear deal, which lifted punishing sanctions on Iran in exchange for limits on and inspections of its nuclear program. Instead he is expected to decertify the deal. That would kick it back to congress to decide whether to reimpose sanctions but congress, robin, really has no appetite to do this. But it sounds though -- seems like a compromise of some sort. Reporter: It does because this way he can say he did something about the deal but not completely rip it up which would infuriate the others who signed on to the deal but this will still Ben as very controversial, robin. All right, Martha, and George will be anchoring ABC's live coverage of the president's remarks on Iran today starting at 1:45 eastern.

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