The new rules will have some exceptions for people who have visited any of those four countries for business, government, humanitarian or journalistic reasons. But they are not clear as to how the U.S. will define dual nationality, which is likely to further frustrate members of the Iranian, Iraqi, Sudanese and Syrian diaspora — many of whom have never visited those four countries.

Republicans, especially those opposed to the Iran nuclear deal, are likely to be unhappy with some of the exceptions, especially if they go easy on people who have visited for business reasons. Some have already warned the Obama administration to take a hard line on the visa rules as they pertain to Iran.

POLITICO reported on the new rules early Thursday morning, ahead of the official mid-day announcement, because the U.S. embassies in Germany and Britain accidentally, and temporarily, posted them on their websites. The administration, meanwhile, briefed congressional staffers Thursday morning about its plans.