When Shreya Mishra Reddy was admitted to Harvard University in 2023, her parents were "ecstatic".

It is "the ultimate school that anybody in India wants to get into," she tells the BBC.

Now, with graduation around the corner, she has had to break the bad news to her family: she may not graduate in July from the executive leadership programme after the Trump administration moved to stop Harvard from enrolling international students "as a result of their failure to adhere to the law".

"It has been very difficult for my family to hear. They're still trying to process it," she said.

Ms Reddy is one of around 6,800 international students at Harvard, who make up more than 27% of its enrolments this year. They are a crucial source of revenue for the Ivy League school. About a third of its foreign students are from China, and more than 700 are Indian, such as Ms Reddy.

All of them are now unsure of what to expect next. Harvard has called the move "unlawful", which could lead to a legal challenge.

But that leaves the students' futures in limbo, be it those who are waiting to enrol this summer, or are halfway through college, or even those awaiting graduation whose work opportunities are tied to their student visas.

Those who are already at Harvard would have to transfer to other American universities to remain in the US and retain their visas.

"I hope Harvard will stand for us and some solution can be worked out," Ms Reddy says.

The university has said it is "fully committed to maintaining [its] ability to host our international students and scholars, who hail from more than 140 countries and enrich the University – and this nation – immeasurably".

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. And it also froze nearly $3bn in federal grants, which Harvard is challenging in court.

Still, Thursday's announcement 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.

The Trump administration seemed to single China out when it accused Harvard of "coordinating with the Chinese Communist Party" in its statement.

Beijing responded on Friday by criticising the "politicisation" of education.

It said the move would "only harm the image and international standing of the United States", urging for the ban to be withdrawn "as soon as possible".

"None of this is what we've signed up for," says 20-year-old Abdullah Shahid Sial from Pakistan, a very vocal student activist.

A junior majoring in applied mathematics and economics, he was one of only two Pakistani undergraduate students admitted to Harvard in 2023.

He was also the first person in his family to study abroad. It was a "massive" moment for them, he says.

The situation he now finds himself in, he adds, is "ridiculous and dehumanising".

Both Ms Reddy and Mr Sial said foreign students apply to go to college in the US because they see it as a welcoming place where opportunities abound.

"You have so much to learn from different cultures, from people of different backgrounds. And everybody really valued that," Ms Reddy says, adding that this had been her experience at Harvard so far.

But Mr Sial says that has changed more recently and foreign students no longer feel welcome - the Trump administration has revoked hundreds of student visas and even detained students on campuses across the country. Many of them were linked to pro-Palestinian protests.

Now, Mr Sial adds, there is a lot of fear and uncertainty in the international student community.

That has only been exacerbated by the latest development. A postgraduate student from South Korea says she is having second thoughts about going home for the summer because she fears she won't be able to re-enter the US.

She did not want to reveal her name because she is worried that might affect her chances of staying in the US. She is one year away from graduating.

She said she had a gruelling semester and had been looking forward to "reuniting with friends and family" - until now.

The anxiety among foreign students is palpable, says Jiang Fangzhou, who is reading public administration in Harvard Kennedy School.

"We might have to leave immediately but people have their lives here - apartments, leases, classes and community. These are not things you can walk away from overnight."

And the ban doesn't just affect current students, the 30-year-old New Zealander says.

"Think about the incoming ones, people who already turned down offers from other schools and planned their lives around Harvard. They're totally stuck now."