A Q&A on the executive order has been released by Customs and Border Protection (CBP) and is available here: https://www.cbp.gov/border-security/protecting-nation-foreign-terrorist-entry-united-states.

The new guidance provides an answer to the question: What does it means to be “from one of the seven countries”? A: “Travelers are being treated according to the travel document they present.” However, citizens and nationals of the named countries who may be dual nationals and have alternate travel documents should still be prepared for potential difficulty boarding the plane or delays upon entry to US.

In addition, CBP has advised that the Deparments of State and Homeland Security can review individual cases and grant waivers on a case-by-case basis if that individual’s admission to the United States is deemed to be in the national interest and they do not pose a national security threat.