President Donald Trump has signed a proclamation restricting the entry of foreign students who are wanting to participate in exchange

President Donald Trump has signed a proclamation to suspend international visas for new students at Harvard University, the White House announced Wednesday, in a dramatic escalation of its efforts to block foreign nationals from enrolling at the elite university.

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.