CONCORD, N.H. (AP) — More U.S. colleges and universities are advising international students to return to campus ahead of President-elect Donald Trump’s inauguration because they fear he could impose travel bans as he did during his first term .

More than a dozen schools have issued warnings, even as Trump’s plans remain uncertain. At some schools, the spring semester begins before Trump takes office, meaning students may need to be back in class anyway. But for anyone whose ability to stay in the United States depends on an academic visa, he said it’s best to reduce risk and return to campus before Jan. 20.

Here’s a look at what Trump said and did and how schools and students are preparing for his second term:

What has Trump done in the past?

Trump issued an executive order in January 2017 that banned travel to the United States by citizens of seven predominantly Muslim countries: Iraq, Syria, Iran, Sudan, Libya, Somalia and Yemen. Travelers from these countries were either denied entry to their flights or detained at U.S. airports after landing. These included students and teachers as well as business people, tourists and visitors from friends and family.

Trump later removed some countries and added others to the list – 15 nations were affected at some point during his presidency. According to the US State Department, more than 40,000 people were ultimately denied visas because of the ban. President Joe Biden repealed the orders when he took office in 2021.

How are students affected?

More than 1.1 million international students were enrolled in U.S. colleges and universities in the 2023-24 school year, according to Open Doors, a data project funded in part by the U.S. State Department. Students from India and China make up more than half of all international students in the U.S., and about 43,800 come from the 15 countries affected by Trump’s travel restrictions.

Jacky Li, a third-year environmental studies student at the University of California, Berkeley, will travel to China on December 21st and return on January 16th. Although he had made his plans months before Berkeley officials sent the notice, he said concern is growing among international students.

“With today’s geopolitical tensions around the world, there is a fear that this kind of restriction will spread to a larger community, so the fear is definitely there,” said Li, who urged Trump to support important academic research instead to thwart them.

“If the United States is truly a champion of academic freedom, you should not restrict this type of communication between different countries in the world,” he said.

What could Trump do now?

Trump’s transition team did not respond to questions on the subject this week, but in the past he has said he would revive and expand the travel ban and promised new “ideological vetting” for non-U.S. citizens to exclude “dangerous lunatics and haters.” Fanatics and madmen.”

“We are not bringing in anyone from Gaza, Syria, Somalia, Yemen or Libya or anywhere else who threatens our security,” Trump said at an October 2023 campaign rally in Iowa.

In response to campus protests, Trump also promised to “revoke the student visas of radical anti-American and anti-Semitic aliens at our colleges and universities.”

What do schools say to their students?

School officials have advised international students traveling home for winter break to return before Inauguration Day and prepare for possible immigration delays.

The list includes Ivy League universities like Harvard and Brown, Boston schools like Northeastern University and the Massachusetts Institute of Technology, and other schools across the country, from Johns Hopkins University to the University of Southern California. Some offer classes that begin the day after Inauguration Day.

Cornell University told its students that a travel ban on the 13 countries Trump previously targeted “will likely take effect soon after the inauguration” and that new countries, notably China and India, could be added to the list. Students, faculty and staff from these countries have been advised to return to campus before the start of the semester on January 21st.

Other schools didn’t go so far as to say a ban was likely, but rather advised students to plan ahead and prepare for delays.