BERKELEY, Calif. – Conservative students at the University of California Berkeley are threatening to sue the school for violating their constitutionally protected free speech rights by blocking conservative commentator Ann Coulter from speaking on campus.

After lengthy negotiations over Coulter’s immigration speech scheduled for April 27, Berkeley College Republicans gave UC Berkeley administrators an ultimatum: Allow Coulter to speak as scheduled or face a federal lawsuit, SF Gate reports.

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The students gave the university until 5 p.m. Friday to decide.

On Tuesday, UC Berkeley canceled Coulter’s scheduled talk, citing an inability to protect Coulter and others against inevitable violent protests from social justice warriors on campus who sparked a riot in February that canceled a planned speech by former Breitbart editor Milo Yiannopoulos.

“Campus officials said they had received ‘specific intelligence’ about anti-Coulter violence and suggested the talk could be rescheduled for September,” according to the news site.

The decision came after Coulter repeatedly agreed to an evolving list of demands from school officials, Coulter told Fox News’ Tucker Carlson on Wednesday.

“They kept piling on requirements, ruses. You can’t speak in the evening, you have to speak during the daytime when kids are in classes. We’re not sure which room you’re going to use, we won’t tell you until the last minute. You have to exclude everyone except students,” Coulter said. “And although the (student) groups … the intermediaries kept encouraging me to say ‘you know, this is unfair, they never do this to liberals,’ I kept saying, ‘nope, I’ll do it, okay, okay.’

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“So I agreed to all their demands and I wake up this morning and they sent out a letter saying how much they love the First Amendment and freedom of speech and they’re so committed to it, but we’re just canceling her anyway.”

The next day, on Thursday, UC Berkeley officials reversed course, sort of.

They offered to reschedule the speech for May 2 instead, a date that coincides with the school’s “Dead Week,” when students are not in class and cramming for finals.

“Our police department has made it clear that they have very specific intelligence regarding threats that could pose a grave danger to the speaker, attendees and those who may wish to lawfully protest the event,” Chancellor Nicholas Dirks wrote in a statement, according to The Washington Post. “At the same time, we respect and support Ms. Coulter’s own First Amendment rights.”

After the decision to cancel on Wednesday, Dirks said he asked staffers to “look beyond the usual venues we use for large public gatherings to see if there might be a protectable space for this event. … Fortunately, that expanded search identified an appropriate, protectable venue.”

“It has nothing to do with anyone’s political views. We believe in unqualified support to the First Amendment. But we also have an unqualified focus on safety of our students,” Berkeley spokesman Dan Mogulof told the Post. “We are going to be making a concerted effort to explain the reasons behind this.”

Coulter rejected the offer and explained that she already spent money to come to Berkeley on April 27, and is not available on May 2. Berkeley College Republicans and the Young America’s Foundation, a national group helping with Coulter’s $20,000 speaking fee, then hired high-powered San Francisco attorney Harmeet Dhillon to lean on college officials to reconsider.

Dhillon sent a four-page letter to Vice Chancellor Stephen Sutton pointing out that the school has not restricted “innumerable speeches by prominent liberal speakers” including former Clinton advisor Maria Echaveste – scheduled to speak in the same series on immigration as Coulter – or Mexican President Vicente Fox, who was on campus this week to speak out against Trump, SF Gate reports.

Dhillon also highlighted “UC Berkeley’s similar silencing of two other speakers” – Yiannopoulos and David Horowitz – who were “canceled at the last minute on the pretext of being unable to provide adequate security.”

The practice of shunning conservative speakers equates to “a ‘heckler’s veo’ to suppress the free speech rights of speakers properly invited” by conservative students, Dhillon wrote.

“It is ironic that UC Berkeley, known to many Americans as the birthplace of the Free-Speech Movement, is now leading the vanguard to silence conservative speech on campus,” the letter read.

Dhillon gave officials until the end of business hours on Friday to “cooperate with Ms. Coulter’s planned speech by providing a similar forum to her as that provided to other prominent speakers this month” or her clients “will seek relief in federal court, including claims for injunctive relief and damages.”

Coulter, meanwhile, has vowed to deliver her speech on April 27, with or without UC Berkeley’s blessing.

“I am giving this speech,” she told Carlson. “What are they going to do, arrest me?”