BOSTON - US President Donald Trump on Wednesday suspended for an initial six months the entry into the United States of foreign nationals seeking to study or participate in exchange programs at Harvard University, amid an escalating dispute with the Ivy League school.

Trump's proclamation cited national security concerns as a justification for barring international students from entering the United States to pursue studies at the Cambridge, Massachusetts-based university.

Harvard in a statement called Trump's proclamation "yet another illegal retaliatory step taken by the Administration in violation of Harvard's First Amendment rights."

"Harvard will continue to protect its international students," it added.

Reuters