President Donald Trump 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 foreigners from enrolling at the elite university.

President Donald Trump took direct action against Harvard University Wednesday night by issuing a proclamation barring the university's international students from entering the U.S. — a move Harvard called "illegal.

President Donald Trump is moving to block nearly all foreign students from entering the country to attend Harvard University, his latest attempt to choke the Ivy League school from an international pipeline that accounts for a quarter of the student body.