The sharp escalation in Trump's longstanding feud with the elite Cambridge, Massachusetts-based college came as tensions simmer between Washington and Beijing over trade and other issues.

Around 1,300 Chinese students are currently enrolled at Harvard, according to official figures, and hundreds of thousands more attend other universities in a country long viewed by many in China as a beacon of academic freedom and rigour.

Admissions consultant Xiaofeng Wan, who advises overseas students on getting into top US universities, told AFP he had been on the phone with panicked clients all evening.

"I've got questions not only from families but also from school-based college counsellors in China as well, including principals of high schools," Wan said, speaking by phone from Massachusetts.

"They were all shocked by the news. They could not believe that this actually happened."

On the streets of Beijing on Friday, budding international students told AFP they feared their scholarly ambitions were now hanging in the balance.

"I'm a bit panicked to be honest," said Jennifer, who was planning to attend college in the United States this autumn.

While she did not intend to apply to Harvard, "budget cuts and enrollment restrictions affect all universities in the United States, regardless of where you apply", said the 20-year-old, who declined to give her surname.

Jennifer said she worried Trump's policies would "affect my chances of getting admitted" to her top choice, Ohio State University, which said last month that the federal government had revoked the visas of at least seven of its international students.

"My classmates and I feel like we don't have any particularly good solutions to this issue, other than being pessimistic," she said.

- 'Sense of panic' -

Trump has blasted Harvard for refusing to submit to government oversight on admissions and hiring, and has repeatedly claimed it is rife with anti-Semitism and "woke" liberal ideology.

US Homeland Security Secretary Kristi Noem wrote on X that Thursday's move would also hold Harvard "accountable for... coordinating with the Chinese Communist Party on its campus", without giving details.

In a swift response, Harvard slammed the revocation as "unlawful".

China's foreign ministry was quick to criticise the move on Friday, saying the ban would "only harm the image and international standing of the United States".

The number of Chinese students at American universities has been declining in recent years but still stood at nearly 280,000 in the 2023-24 academic year, according to figures from the US State Department and the Institute of International Education.

Entire industries have sprung up in China in recent decades as millions of people have risen into the middle class and ploughed money into lucrative foreign educations for their children.

"There's a great sense of panic among the international student community, both current and prospective," said Wan, the Massachusetts-based consultant.

They are "concerned that the country of the US is closing the door on them", he said.

"(It's) not helpful for a country that thrives on talents from abroad... and whose fundamental engine in research is supported by international talent."