Ahead of a federal hearing over Harvard University’s ability to enroll international students, the acting director of the U.S. Immigration and Customs Enforcement issued a letter giving the school 30 days to challenge the administration’s revocation of that certification.

The letter formally notifies the school that its Student and Exchange Visitor Program certification would be withdrawn — but backtracks from the administration’s earlier stance by giving Harvard 30 days to achieve compliance.

“Your school has 30 calendar days from the date of service of this Notice to submit written representations under oath and supported by documentary evidence, setting forth the reasons why SEVP should not withdraw your school’s certification,” the notice said. “If SEVP certification is withdrawn, your school will then no longer be approved to enroll or continue to educate nonimmigrant students.”

The notice comes one week after Secretary of Homeland Security Kristi Noem announced she had ordered the termination of Harvard University’s Student and Exchange Visitor Program certification.

As thousands of Harvard University students and their families gather this morning for commencement, a federal judge is set to hear arguments Thursday morning over whether to extend an order blocking the Trump administration from stripping Harvard of its SEVP certification.

In an escalation of Trump’s recent attacks on Harvard, the Department of Homeland Security last week revoked the school’s Student and Exchange Visitor Program certification, throwing the status of the school’s nearly 7,000 international students into immediate uncertainty.

Harvard quickly sued to block the policy, arguing the students have become “pawns in the government’s escalating campaign of retaliation” — and a federal judge on Friday granted a temporary order that barred the Trump administration from revoking the school’s SEVP certification.

U.S. District Allison Burroughs, an Obama appointee, granted the temporary order within hours of Harvard filing its lawsuit, writing that the school was likely to suffer “immediate and irreparable injury” if the policy was enacted. Harvard’s lawyers have argued that nearly every one of its international students would have to transfer or drop out if the Trump administration carries out the revocation.

“With the stroke of a pen, the government has sought to erase a quarter of Harvard’s student body, international students who contribute significantly to the University and its mission,” their lawsuit said.

Arguing that the Trump administration actions are part of a “campaign to coerce Harvard into surrendering its First Amendment rights,” Harvard has alleged that the SEVP revocation is unlawful because it violates the school’s free speech rights; that the policy is arbitrary and therefore violates the Administrative Procedure Act; and that the policy runs roughshod over the school’s due process protections because it was not given the opportunity to respond to the revocation.

“The surrounding events, and Defendants’ express statements, make clear that the Department of Homeland Security took these actions not for any valid reason, but purely as punishment for Harvard’s speech, its perceived viewpoint, and its refusal to surrender its academic independence or relinquish its constitutional rights,” the lawsuit argued.

“It is the latest act by the government in clear retaliation for Harvard exercising its First Amendment rights to reject the government’s demands to control Harvard’s governance, curriculum, and the ‘ideology’ of its faculty and students,” said the suit.

DHS officials have said that the revocation was necessary because Harvard failed to turn over information about international students — including disciplinary records — as requested by the Trump administration.

“It is a privilege, not a right, for universities to enroll foreign students and benefit from their higher tuition payments to help pad their multibillion-dollar endowments. Harvard had plenty of opportunity to do the right thing. It refused.’ DHS Secretary Kristi Noem said in a statement last week.

Harvard is also fighting the Trump administration’s attempt to freeze more $2.2 billion in grants and $60 million in contracts to the school. Harvard filed a separate lawsuit to challenge the funding freeze in April, and the next hearing in that case is set for July.

Trump has continued to ratchet up the pressure on the school over the last two months, threatening to revoke the school’s tax-exempt status, directing his administration to cancel contracts with the school, and continuing to demand information on international students. Speaking to reporters on Wednesday, Trump suggested that Harvard should cap the number of international students to 15% of the school’s total student body.

“We have people who want to go to Harvard and other schools, they can’t get in because we have foreign students there. But I want to make sure that the foreign students are people that can love our country,” Trump said.