Nicholas Kamm/AFP/Getty Images President Donald Trump is expected to sign an executive order that would keep people from certain countries from coming to the U.S., at least tem

WASHINGTON ― Immigration attorney Ally Bolour got a call on Wednesday from a client worried about President Donald Trump’s expected executive order that could temporarily shut down travel from majority-Muslim countries.

The client is planning a trip to Puerto Vallarta, Mexico, for his birthday. He lives in the U.S. legally as a green-card holder, but he’s from Iran ― one of the countries Trump will likely single out for restrictions. The man, Amir, who asked to be identified only by his first name, already paid for his flight and hotel, but asked Bolour for advice.

“If I were you, I wouldn’t go,” Bolour said he told Amir. “It’s too uncertain.”

Trump has not yet signed an executive order to keep people from certain countries from coming to the United States. But already, news that he is considering such restrictions is having a dramatic impact. Leaked drafts indicate it could be harder or even impossible for people from seven countries to get into the U.S. ― even if they hold green cards.

With Trump, you cannot take any risks. Hassan Shibly, executive director of Council on American-Islamic Relations Florida

Immigration attorneys and advocacy groups said they were being inundated with questions from people legally in the U.S. wondering whether it would be safe for them to travel. Some want to leave the country to attend a parent’s funeral. Students hoped to travel home for spring break. Couples have plans for a vacation together. All of them, lawyers are advising, should stay put.

“I don’t want to make people scared for no reason, but I think caution is best right now until we see what that exact language will be,” said Nermeen Arastu, clinical law professor at CUNY School of Law. “If you’re a not U.S. citizen, don’t leave right now.”

Hassan Shibly, executive director of Council on American-Islamic Relations’ Florida chapter, said a source in the federal government advised him to tell people that non-citizens who are natives of the countries mentioned in drafts of Trump’s executive order should not leave the U.S. for the time being, even if they hold green cards.

“We definitely need people to take caution at this point,” Shibly said. “With Trump, you cannot take any risks. You cannot take any principle of liberty or justice for granted. We cannot let our guard down.”

The attorneys and experts said they have spent recent days trying to calm immigrants and Muslim communities. Offering advice before Trump signs the order, without knowing the final language, is a particular challenge, they pointed out. They don’t know, for example, whether it will apply to green-card holders and what countries will be targeted.

“These orders are going to have an impact on the daily life of hundreds of thousands of individuals in this country who are here through different visa programs,” said Abed Ayoub, legal director at the American-Arab Anti-Discrimination Committee.

Immigration attorney Hassan Ahmad cautioned against blanket statements of advice about whether to leave or stay. The order isn’t signed, he said, and many immigration cases are different. Some people may be seeking asylum, for example, in a different situation than someone with a green card.

“There is no easy answer, unfortunately, and that’s a really tough pill to swallow,” Ahmad said.

Amir is still unsure what to do about his trip. When he planned the vacation, he never imagined he’d have to worry about presidential politics, he said.

Amir, who is gay, came to the U.S. 11 years ago as a student and received asylum based on persecution in Iran over his sexual orientation, he said. He has held a green card for five years and has traveled outside the U.S. multiple times for work and pleasure. He hasn’t been back to Iran.

Amir said his whole life is in the U.S.: a job, a house, a partner and friends. He said he’ll make up his mind about his vacation after he sees what Trump’s executive order actually says, and whether green-card holders already outside the U.S. have trouble returning.

“Let’s say I go to Mexico and want to come back and they don’t let me in. Where am I going to go?” he asked. “I can’t go back to my home country. I don’t have any other place to go.”

Sharaf Mowjood contributed reporting.

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