Airlines are perhaps the companies most directly affected by the order to ban citizens of seven countries from entry into the United States, even those with previously valid visas or US green cards.

The airlines have no choice but to cooperate with US Customs and Border Patrol instructions, even as they deal with passengers and, surely, employees who can no longer enter the United States.

The Verge has reached out to a number of airlines to get comment and we will be updating this post as we hear back.

Update January 29th, 12:37AM ET: CNN reports that there was some confusion at the Department of Homeland Security over whether the order affected lawful permanent residents — also known as green card holders. Guidance sent to airlines included language stating that “lawful permanent residents are not included [in the ban] and may continue to travel to the USA.” This language turned out to be incorrect, though a number of green card holders were eventually allowed to enter the country after significant delays. This would explain the inconsistent language in several of the statements issued by airlines below.

Delta Air Lines

An Executive Order issued on Jan. 27 has suspended for 90 days the entry into the United States of most immigrant and non-immigrant "aliens [8 USC 11101(a)(3)]" from the nations of Libya, Iran, Iraq, Somalia, Sudan, Syria and Yemen.  Entry of nationals from Syria as refugees is suspended indefinitely.

Delta will make every effort to contact impacted customers with flexible rebooking options, including refunds. Worldwide customer contact information can be found here.

United Airlines

We are aware of the directive and are working with the federal government to comply.

Effective immediately and until further notice, due to an executive order, the U.S. Department of State has revoked immigrant and non-immigrant visas for travelers to the United States from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen. Please note that this does not affect U.S. resident card holders. Customers who meet these qualifications will not be able to board a United- or United Express-operated flight to the U.S. If you have travel plans that are affected by this new regulation, please contact the United Customer Contact Center. Additional information is available through the Department of State.

Southwest Airlines

Given our route map, we have no indications of any impacts on Southwest Airlines. 

Etihad Airways

As a result of the Executive Order signed by the U.S. President on 27 January 2017, U.S. immigration entry requirements for nationals of Iran, Iraq, Sudan, Somalia, Syria, Yemen and Libya have changed. Effective immediately, nationals from these countries may only travel to the U.S. if they hold one of the following documents:

· a valid U.S. Lawful Permanent Resident (LPR) card, commonly known as a “Green Card”;

· Diplomatic visa;

· North Atlantic Treaty Organization (NATO) visas;

· C-2 visas for travel to the United Nations;

· G-1, G-2, G-3 and G-4 visas; or

· valid passport from another country that allows U.S. entry along with a valid U.S. visa or ESTA as applicable for that passport.

For more information, please contact a U.S. Consulate or visit the U.S. Customs and Border Protection website.

Affected passengers holding tickets to travel on Etihad Airways should contact their booking agent if they require amendments to travel arrangements.

British Airways

We always meet our obligations under international immigration agreements.

We are offering affected customers a refund for their travel to the US, or the opportunity to rebook their flight.

Emirates

A very small number of our passengers travelling were affected by the new U.S. immigration entry requirements implemented by the U.S. Customs and Border Protection today (28 January 2017). Where applicable, we are assisting the affected travellers with their flight re-bookings. Passengers are responsible for ensuring they have the required documents for their travel.

Virgin Atlantic

We always endeavour to do the right thing by our customers and we will look into all options for those affected, including rebooking travel for a later date, alternative destinations for customers no longer wishing to travel to the U.S., or full refunds. Full details are available for our customers at https://www.virginatlantic.com/gb/en/travel-information/travel-news.html . We will continue to monitor the executive orders issued by the United States and we will adapt our policy should there be a need to do so.

KLM

On 28 January 2017, President Trump of the United States of America signed an executive order that has immediate consequences for passengers from seven countries: Iraq, Iran, Syria, Sudan, Somalia, Libya, and Yemen. As a result, KLM was compelled to inform seven passengers on Saturday that they would not be able to fly to the USA.

Like all other airlines, KLM has to comply with the entrance requirements that countries set for travellers. Airlines are not permitted to carry passengers who do not meet those entrance requirements. In this, KLM complies with the aviation authorities’ international agreements.

KLM regrets the inconvenience caused to its passengers who were confronted with this sudden change of circumstances. Although the fact that these passengers were unable to fly to the USA lies entirely outside KLM’s sphere of influence, we decided to offer these passengers a voucher equivalent in value to the flight they were unable to take to the USA. KLM thereby hopes to alleviate to some degree the inconvenience caused by the decision taken by the American authorities.

KLM now informs affected passengers prior to departure. Passengers who were already on their way to Schiphol have been offered a free flight back to where they departed from. No KLM passenger has got stuck anywhere.

Lufthansa

Like in other cases, passengers and airlines are obliged to comply to the applicable immigration regulations. There have only been a few recorded cases where Lufthansa has not allowed passengers to travel to the USA. Customers who have been affected by these new regulations are offered a free rebooking or are given a full refund.