Trump on Friday put a four-months hold on US refugee admissions saying he wants more strictures and suspended the Syrian refugee program indefinitely.

Trump has banned entry from seven Muslim-majority countries – Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen – for at least 90 days, saying that the move would protect Americans from terrorist attacks. In practice, this has barred even legal US residents, such as green card holders, from re-entry into the country.

The bans took effect immediately causing havoc and confusion. Five Iraqi passengers and one Yemeni were barred from boarding an EgyptAir flight from Cairo to New York on Saturday and were re-directed to flights headed for their home countries despite holding valid visas.

Trump prioritized refugee claims on the basis of religious persecution, so long as the applicant belongs to a religion that is minority in their country of origin. The move is to prioritize Christians from the Middle East over Muslims.

The Council on American-Islamic Relations said the order targets Muslims because of their faith, contravening the US Constitutional right to freedom of religion. Democrats and civil rights attorneys have excoriated the order. Immigration lawyers and employers have warned many people not to leave the US for fear they could be barred from re-entering.