Atlanta/Los Angeles: Global airlines are struggling to comply with new travel restrictions after being caught flat-footed by President Donald Trump’s executive order blocking visitors from seven predominantly Muslim nations.

US carriers didn’t get advance notice of the travel ban or briefings from government officials on how it should be implemented, people familiar with the matter said.

The order was causing chaos at airports in the US and abroad as border agents blocked travelers from entering the country and airlines barred visa-holders from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen, as well as people from those countries who are lawful US residents, from getting on planes to the country.

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“We are aware of the directive and are working with the federal government to comply," United Continental Holdings Inc. spokesman Luke Punzenberger said in a statement.

The president’s order has the potential to impose costs on the airlines, which are struggling to understand its terms, said Robert Mann, president of aviation consultancy R.W. Mann & Co. Carriers are responsible for returning passengers to where their travel began if they were brought to the US improperly, he said.

“It’s very confusing for airlines," he said in an interview. “They literally don’t have a reference point now on how they can accommodate their customers."

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Airlines follow a detailed set of government regulations specifying who is allowed into the US. Based on news reports, Mann said it appears that Trump issued his order without giving carriers a chance to change their existing rule books.

Airline reaction

Airlines worldwide reacted to Trump’s order on Saturday:

American Airlines Group Inc. and industry trade group Airlines for America declined to comment, referring questions to the US government.

Immigration lawyers

“It is imperative we find the right balance between security and facilitation, and we stand ready to support the administration and Congress to achieve this goal," said Roger Dow, chief executive officer of the US Travel Association, a non-profit lobbying group.

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Lawyers “are trying to makes sense of what happened," said Christine Alden, an immigration attorney in Miami. “It’s all really far-reaching. It’s going to affect businesses, families and students going back to school," she said.

The US has treaties with some of the targeted counties that allow investors to visit the US under the E-2 visa program, she said. Those people won’t be allowed to come run their businesses. Oil companies, tech companies and others that depend on foreign workers may see them stranded overseas. Bloomberg