In a significant reversal, Columbia University said Friday that all undergraduate courses would be conducted online for the upcoming fall semester. The university is also backing away from its plan to bring back 60% of its undergraduate students to campus, a decision which drew sharp criticism from the community.

Lee Bollinger, the university president, sent an email to students informing them of the new decision.

"With few undergraduate students living on campus, we have decided that all undergraduate courses will be virtual," he said.

While he noted that Columbia had the "physical capacity to conduct many undergraduate courses in person," he said that because students would be spread across so many locations and under different circumstances, that "online instruction is the only realistic approach."

Bollinger attributed part of the reason for the change to New York's strict 14-day quarantine requirement that has applied to more than 30 U.S. states or territories with high infection levels.

"While I am supportive of the measures New York State has imposed, and while I have no doubt that we could ensure a safe quarantine period from a public health standpoint, two weeks is a long time to endure isolation, especially for students who will be leaving home for the first time."

Columbia now joins a list of other major universities, including Harvard, Princeton, and Johns Hopkins, that have decided to move exclusively to online instruction.

Unlike Harvard, however, Columbia will allow graduate schools to hold in-person classes. Bollinger said that "approximately 40 percent of all graduate courses offered this fall will be hybrid or in-person," including his own First Amendment course at Columbia Law School.

From the start, Columbia's decision to conduct in-person classes was fraught with controversy. Neighbors, led by the Morningside Heights Community Coalition, expressed concern that the return of so many students from across the country would endanger the health of residents.

The university initially gave faculty a choice of teaching in-person or virtually, but when too few signed up for the former, a Columbia official late last month sent an email strongly encouraging its college faculty and teaching assistants to hold in-person classes.

“We will be safer in class than in grocery stores," wrote Amy Hugerford, Columbia's executive vice president of arts and sciences.

The missive caused an uproar among faculty members, some of whom accused the university of valuing money over their safety. The need to offer in-person classes was all the more pressing for first-year international students, who cannot quality for a student visa if their classes are only online.

And last Friday, Columbia angered international graduate students after announcing that it would pay doctoral students to teach only if they are in the United States. Many students who returned to their homes abroad had intended to teach remotely.

Facing pressure, officials on Monday said they would walk back the plan and issue a new policy.

Columbia's decision will likely put further pressure on New York University, which has said it would offer a mix of online and in-person classes in the fall. NYU has already announced undergraduate move-in days, which included early dates this month for those who would need to quarantine.

Governor Andrew Cuomo has said that any college reopening plan must be approved by the state Department of Health.