Emirates airline has changed pilot and flight attendant rosters on flights to the US following the sudden US travel ban on seven Muslim-majority countries, but it said US flights continue to operate to schedule, a report said.

The world's largest long-haul carrier, who flies daily to 11 US cities, has made "the necessary adjustments to our crewing, to comply with the latest requirements," the Saudi Press Agency (SPA) reported, citing an Emirates spokesperson.

President Donald Trump on Friday temporarily suspended the entry of people from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen. The decision caught airlines off guard, according to the International Air Transport Association.

The ban applies to pilots and flight attendants from the seven countries, even though all flight crew who are not US citizens already need a special visa to enter the country.

Another Emirates spokeswoman said the impact of the ban on operations would be minimal. The airline employs over 23,000 flight attendants and about four thousand pilots from around the world, including the United States, Europe and the Middle East.

Meanwhile, an Etihad Airways spokesman said the airline has "taken steps to ensure there will be no issues for flights departing over the coming weeks."

But amid confusion over enforcing the ban, it is unclear if the ban applies to dual nationals - those who hold one passport from a country on the list and another from a non-US country that is not.

Etihad said on its website that dual citizens could travel to the US using their non-banned passport. Iata has told its members that the ban does not apply to dual nationals if they have a passport not on the list, the report said, citing Reuters.

Qatar Airways declined to comment on the impact of the ban on flight operations, although on Saturday it issued a statement on its website that passengers would need a green card or diplomatic visa to enter the US Emirates and Etihad issued similar statements.