President Donald Trump said on Friday he planned to strip Harvard University of its tax-exempt status, setting up another potential legal fight with the Ivy League school amid his wider crackdown on elite universities and the US education system.

“We are going to be taking away Harvard’s Tax Exempt Status. It’s what they deserve!” Trump said in a post on his social media platform, without specifying when he might take action.

Representatives for the Internal Revenue Service did not immediately respond to a request for comment on Trump’s post and whether it was revoking the university’s tax-exempt status.

Harvard, in a statement, said the move would be unlawful and unprecedented.

“There is no legal basis to rescind Harvard’s tax-exempt status,” the Boston-area school said. “The unlawful use of this instrument more broadly would have grave consequences for the future of higher education in America.”

It would also cut money available for student scholarships, medical research and technological advancements that drive economic growth, Harvard added.

Since taking office in January, Trump has targeted major US universities by freezing federal funding, launching investigations, revoking student visas and making other demands. He has said higher education has been gripped by antisemitic, anti-American, Marxist and radical left ideologies.

Under federal law, the president cannot request that the IRS, which determines whether an organization can have or maintain tax-exempt status, investigate organizations.

Most universities are exempt from federal income tax under the US tax code because they are deemed to be operated exclusively for public educational purposes.

Trump’s administration has escalated its fight against Harvard in recent weeks, probing its nearly $9 billion in federal funding, seeking details on its foreign ties and threatening its ability to enroll foreign students. The administration has also demanded a ban on diversity, equity and inclusion practices, a crackdown on some pro-Palestinian groups and a mask ban.

Harvard has pushed back, suing the administration over the halted US research funding and other demands, and joining more than 200 university and college presidents in protesting Trump’s higher education policies.

Trump said he was considering an end to Harvard’s tax-exempt status in a separate social media post on April 15, when annual US tax returns are due, but did not say how he would do it.

White House spokesperson Harrison Fields last month said any forthcoming IRS actions were independent of the president and that any tax status investigations were initiated before Trump’s post.