Durham, N.C. — More than 100 university presidents nationwide have asked President Barack Obama and Congress for legislation that would allow foreign-born students to remain in the U.S. after graduation.

Duke University President Richard Brodhead, who signed the appeal along with University of North Carolina at Chapel Hill Chancellor Holden Thorp and North Carolina State University Chancellor Randy Woodson, said many of the nearly 2,000 foreign graduate students at Duke are engaged in cutting-edge research that could benefit the U.S. economy.

"It's just a paradox that we should prepare these people who have these gifts who want to stay here and work and then send them somewhere else," Brodhead said Friday, noting thousands of foreign students return to their native countries after graduating in the U.S. because their visas expire.

"What we've asked is for a clear path to a green card for international students who come here," he said.

Pan Wu, who came from China to study chemistry at Duke, said he would like to stay in the U.S. after he gets his degree. He said he finds it frustrating that he can study in this country but cannot work here.

"I search on the websites to find job opportunities. It seems like many jobs require you have a green card in the first place, but for a student, how could we get a green card?" Wu said. "It's very important for the international students to have a guarantee to stay here."

Fewer than 300 of the foreign-born graduate students at Duke have permanent residency, or green cards, that allow them to stay in the U.S. after graduation. Brodhead said the U.S. would be better off if everyone who wanted to stay could.

"I would rather have them working here to bring us all forward than be competing with them in another country," he said.