The move against Harvard has huge implications for the million or so international students in the US. And it follows a growing crackdown by the Trump administration on institutes of higher learning, especially those that witnessed major pro-Palestinian protests on campus.
Dozens of them are facing investigations, as the government attempts to overhaul their accreditation process and reshape the way they are run.
The White House first threatened to bar foreign students from Harvard in April, after the university refused to make changes to its hiring, admissions and teaching practices to help fight antisemitism on campus. And it also froze nearly $3bn in federal grants, which Harvard is challenging in court.
Still, Thursday's announcement - which Homeland Security Secretary Kristi Noem said came "as a result of [Harvard's] failure to adhere to the law" - left students reeling.
Chinese student Kat Xie, who is in her second year in a STEM programme, says she is "in shock".
"I had almost forgotten about [the earlier threat of a ban] and then Thursday's announcement suddenly came."
But she adds a part of her had expected "the worst", so she had spent the last few weeks seeking professional advice on how to continue staying in the US.
But the options are "all very troublesome and expensive", she says.




