The recent ban on entry into the USA by nationals of several countries may apply to airline crews, leaving the airline industry struggling to understand the implications of the order, IATA and media reports indicate.

The executive order containing the ban, signed by president Donald Trump on 27 January, "was issued without prior coordination or warning, causing confusion among both airlines and travellers", says IATA in a statement to FlightGlobal.

"It also placed an additional burden on airlines to comply with unclear requirements, bear implement costs and face potential fines for non-compliance," IATA adds.

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The group says it has asked the Trump administration to clarify the new requirements and has urged "all governments to provide sufficient advance coordination so that travellers can clearly understand requirements and airlines can efficiently implement them".

Trump's executive order bans for 90 days entry into the USA of nationals from seven countries: Iraq, Iran, Libya, Sudan, Yemen, Syria and Somalia.

The order describes the highly-controversial move as necessary to ensure that the US conducts adequate screening to protect the country from terrorist threats.

Opponents have described the order as discriminatory, ineffective and non-representative of America's traditional pro-immigration stance.

Though IATA's statement does not address directly questions about the impact to airline crew members, media outlets report that IATA told airlines last week that cabin crew from certain countries would be subject to the ban.

Some airlines, includingEmirates Airline, have already swapped flight crews to ensure compliance with the new travel requirements, media outlets report.

IATA confirms that it sent an "internal memo last week to airlines providing guidance", but the group declines to discuss the memo or provide a copy of the document to FlightGlobal.