A backlash is brewing on the campus of the University of Virginia, where sorority women have been asked to skip fraternity parties this weekend to protect their "safety and well-being."

In a Jan. 20 letter to 16 UVA sororities, national sorority leaders encouraged members not to participate in activities related to "men's bid night" on Saturday and to instead plan alternative "sisterhood events" with 100 percent participation. The letter prompted angry responses from students who felt the request treated them as untrustworthy and undermined efforts to reduce the threat of sexual violence.

The controversy comes at a sensitive time at UVA, which was roiled last year by the death of student Hannah Graham and allegations of a gang rape in a now-discredited Rolling Stone article.

On Tuesday, the university's student council unanimously passed a resolution, co-sponsored by two sorority members, saying the letter "perpetuates the fundamental power dynamics underlying the issue by forbidding sorority women to exercise their agency."

The council's chairman, Abraham Axler, who provided a copy of the letter to NBC News, said the response "is not about people fighting for the right to party. It is a response to what we feel is an infringement on the values of the students of UVA, particularly the value of self-governance."

The sorority members who co-sponsored the resolution did not respond to requests for comment. Neither did the author of the letter, Alpha Delta Pi International President Tammie Pinkston, nor many of the leaders who co-signed. The Inter-Sorority Council declined to comment. The National Panhellenic Conference, which counts the 16 sororities as members, said it had nothing to do with the request, but supported it.

In the letter, Pinkston pointed out that the National Panhellenic Conference had a standing policy saying members would not participate in men's recruitment events. That point was also made by Linda Kahangi, the national executive director of the Alpha Phi sorority, in an emailed statement to NBC News. "This has everything to do with reminding UVA chapters of existing policy and nothing to do with a lack of confidence in smart, strong, women who are members of the Alpha Phi chapter at UVA," she said.

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Students have also protested the request with a Change.org petition and an online letter-writing campaign.

Daillen Culver, a member of a sorority who signed the petition, said she was shocked by the national leadership’s request.

“I think it's a huge step backwards, just in terms of basic women's rights, so I was kind of offended and overall I'm just really frustrated,” she told NBC News.

Culver, a fourth-year student, said she thought the national leadership was aiming for a “quick fix” and had “good intentions,” but was going about it the “completely wrong way.”

“I would just like to turn the focus back to people and to the rape culture and how that is perpetuated on college campuses,” she added. “And not only just on college campuses, but in society as a whole ... I think we need to address that before we try and forbid women from going out to a party on a Saturday night. It's just not a sustainable solution.”

UVA spokesman Anthony P. de Bruyn said the university was not involved in the sororities' request. "With regard to activities scheduled for this weekend, we have confidence in our students' ability to use good judgment, be mindful of one another's safety, and adhere to the new safety practices developed by them and outlined in the recently revised Fraternal Organization Agreements," he said.

"It struck me as exactly the wrong reaction," said UVA law student Claire Collins, who signed the Change.org petition but is not a member of a sorority. "Obviously, there's work to be done, significant work to be done, in how fraternities and sororities handle issues of safety and drinking, especially issues around sexual assault. But the answer isn't telling all the women to stay home."

A moratorium on Greek activities — imposed shortly after the Rolling Stone article was published to allow students and administrators time to implement rules to make Greek life safer — was lifted earlier this month, in time to allow for the annual recruitment of new members, called rush. Bid night is a step in that process.

Members of some UVA sororities told the Washington Post that their chapters had been visited by representatives from their national headquarters telling them they could be suspended or fined if any of them attended bid night parties.

IN-DEPTH

SOCIAL

I went back for frat rush at UVA, my alma mater, and wrote this piece about power, violence, forgetfulness and rape http://t.co/Qf0KIZqwq6 — Jia Tolentino (@jiatolentino) January 28, 2015

— With Katie Wall and Erica Hill