President Donald Trump banned international students from entering the United States to study at Harvard University after his Department of Homeland Security was barred from doing so.

Last week, Judge Allison Burroughs of the U.S. District Court for the District of Massachusetts blocked an attempt by DHS to revoke Harvard’s Student and Exchange Visitor Program, or SEVP, certification. On Wednesday, Trump issued an executive order using a different legal authority to block foreign students from coming to the U.S. to study at Harvard.