Pennsylvania State University president Eric Barron spoke out Sunday against President Trump's executive order banning certain refugees and immigrants from entering the country, saying: "The problems that are surfacing with the order are clear" and asking that it "be ended as soon as possible."

"The best part of Penn State is our people — no matter what country they may call home," Barron said in a statement. "We support all of you."

Barron's remarks appeared to be the most outspoken among Philadelphia-area college officials who sent messages to their campus communities over the weekend. In calling for an end to the executive order, Barron said he was joining with the Association of American Universities, which issued a similar statement Saturday.

Barron also advised foreign members of the campus community to refrain from traveling outside the country "until greater clarity is apparent," saying in a statement that the university would attempt to assist students, faculty, and staff who had questions. He said that to the best of the school's knowledge, none of its students from the affected countries were traveling abroad when the order took effect.

Officials of at least four other local universities issued similar advice over the weekend about putting off foreign travel.

Vincent Price, provost at the University of Pennsylvania, along with other top academic officials, wrote in an email to the Penn community on Sunday: "We advise all nationals from the affected countries to defer travel until there is some clarification of the situation."

"We understand that rapid changes in immigration policy create uncertainty and apprehension for our international students and scholars and the entire Penn community," he wrote. "Penn remains fully committed to these valued members of our community, and to engaging globally to bring the best scholars and students from around the world to our campus."

Penn president Amy Gutmann said the AAU statement "summarizes the concerns that we will be expressing to our government officials."

AAU president Mary Sue Coleman said in a statement that "we recognize the importance of a strong visa process to our nation's security. However, the administration's new order barring the entry or return of individuals from certain countries is already causing damage and should end as quickly as possible."

She said the order "is stranding students who have been approved to study here and are trying to get back to campus and threatens to disrupt the education and research of many others."

Temple University's president, Richard M. Englert, advised in an email to his university Sunday that nationals from the affected countries delay foreign trips, "as it is not clear how re-entry will be affected by the new regulations."

"We are committed to enabling our faculty, students, and visitors – both from the U.S. and from locations around the globe – to contribute to the vitality of the education we provide and the role we play in the local, regional and global economy," Englert said.

John A. Fry, president of Drexel University, issued a statement Sunday afternoon saying students should "defer any planned travel outside the country until the situation can be clarified." He said Drexel has students in several global arenas, including international students on campus, those working in co-ops overseas and those in international research work.

"The chaotic implementation of the presidential order over this weekend -- with key provisions modified, and others halted by federal judges on Saturday -- has only intensified our shared concerns," Fry said. He added that Trump's "blanket ban is antithetical to many of the values we cherish."

Meanwhile, at Princeton University, Deborah Prentice, dean of the faculty, wrote an email to faculty members Friday night that read in part: "We have strongly advised students and scholars who might be affected and who have travel plans in the coming days to defer travel outside of the United States until there is some clarity and legal analysis of the situation or, if they must travel, to seek legal counsel before they do."

Statements from each school also provided campus resources and offices for affected community members to contact for additional questions.