U.S. President Donald Trump's executive order of January 27 bans refugees from all countries from entering the United States for 120 days and bans Syrian refugees from entering indefinitely.
At the same time, the executive order temporarily bans entry into the United States for people from seven predominantly Muslim countries -- Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen -- until more stringent vetting of visas is introduced.
Here is who is affected by the order, titled Protecting The Nation From Foreign Terrorist Entry Into The United States, which took immediate effect when it was issued.
Citizens Of The Seven Blacklisted Countries
Trump's order immediately bans for 90 days -- until April 27 -- aliens from Iran, Iraq, Libya, Somalia, Sudan, Syria, and Yemen from entering the United States on any category of visa: immigrant or nonimmigrant. Visa categories for diplomats, including the United Nations, are excepted.
There remains some confusion about what the executive order means by individuals "from" one of those blacklisted countries, as it is not more clearly defined in the text. A lawyer specializing in immigration law in Washington told RFE/RL that the order does not say whether "from" means holding the citizenship of that country, being born in that country, or both.
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The New York Times reports that U.S. Customs and Border Protection has instructed airlines to stop passengers from the blacklisted countries from boarding flights to the United States and to remove any passengers who do board. The newspaper says airline crew members from the blacklisted countries are also barred from the United States.
There already has been controversy over the status of citizens of the blacklisted countries who arrived in the United States with visas issued before the executive order was announced. Although the executive order banned their entry, judges in four U.S. cities with major international airports ruled that those individuals could not be deported and they were allowed to enter the country.
However, the judges' rulings appear to be limited to people who were already at the U.S. airports at the time of the ban's announcement and so does not seem to suggest exceptions would be made for people arriving in the future with previously issued visas.
The rulings did not challenge the legality of the executive order itself. Under U.S. law, the president has broad powers to control immigration and can suspend the entry of "all aliens or any class of aliens as immigrants or nonimmigrants" if he considers their entry to be harmful to the national interest.
The U.S. administration made clear that the 90-day provision does not mean that travel will automatically be reinstated after that period. During the 90 days, the U.S. government will decide how things will work after April 27.
U.S. Green-Card Holders From The Seven Countries
The order does not expressly spell out restrictions on travel for citizens of the seven countries who are also permanent residents of the United States (green-card holders). On January 29, the secretary of the Department of Homeland Security, John Kelly, said that he deems "the entry of lawful permanent residents to be in the national interest" of the United States.
However, he and other U.S. officials have suggested that green-card holders from the blacklisted countries could face extra screening or questioning as they are admitted.
Dual Nationals Of The Seven Blacklisted Countries
Individuals from the blacklisted countries who also hold the citizenship of another country other than the United States are not permitted to enter the United States for 90 days.
There is some question as to whether exceptions are being made for people whose dual nationality is with a country closely allied with the United States -- for example, Canada or Britain. The British foreign secretary has said Washington assured him the ban did not apply to anyone with dual British citizenship.
Naturalized U.S. Citizens Born In The Seven Countries
The executive order does not apply to U.S. citizens, whether that person is born in the United States or became a citizen through immigration to the United States. That includes people who were born in one of the blacklisted countries and are now naturalized U.S. citizens.
U.S. Citizens Who Travel To The Seven Countries
U.S. citizens who travel to the seven countries are likely to face additional questioning upon their return to the United States. The White House chief of staff, Reince Preibus, told the U.S. network NBC on January 29 that "I would suspect that if you're an American citizen traveling back and forth to Libya, you're likely to be subjected to further questioning when you come into an airport."
Refugees From Syria
The U.S. president's order bars all refugees from Syria -- which has been embroiled in war since 2011, sending millions of refugees abroad -- from entering the United States indefinitely.
However, the order says individuals may be admitted on a case-by-case basis when it is "in the national interest" of the United States, including "when the person is a religious minority in his country of nationality facing religious persecution." Trump has mentioned Christians in Syria as an example, raising the question of their status under the indefinite ban.
All Non-Syrian Refugees
The executive order suspends completely admission of all refugees from anywhere around the world for 120 days. Again, there is the possibility of case-by-case exceptions, including for persecuted religious minorities.
The order also puts a ceiling of 50,000 on the number of refugees the United States will accept from around the world in 2017. That is slightly less than half the ceiling of 110,000 established by former President Barack Obama.
Will Other Countries Be Added To The Blacklist In The Future?
There is no way to know at this time. However, Priebus said the seven countries now blacklisted were chosen because Congress and the Obama administration had identified them previously "as the most watched countries harboring terrorists." He said others could be added but provided no details.
Copyright (c) 2015. RFE/RL, Inc. Reprinted with the permission of Radio Free Europe/Radio Liberty, 1201 Connecticut Ave NW, Ste 400, Washington DC 20036.