The University of Virginia announced Tuesday that it will delay the return of undergraduates by about two weeks, a further sign of the tumult in higher education brought on by the rising threat of the coronavirus pandemic.

Previously, undergraduate students were invited to come this month to the Charlottesville campus known as the Grounds for a fall term with a mix of in-person, remote and hybrid classes.

Now, the term will start remotely for undergrads on Aug. 25, according to U-Va., and any face-to-face instruction they receive will begin after Labor Day. U-Va. leaders cited local and national increases in cases of the novel coronavirus.

The pathogen has killed more than 150,000 Americans, and many states are struggling to control outbreaks. About a third of undergraduates at U-Va. come from out of state.

“In response to these conditions, and based on the advice of U-Va. public health experts, we have decided to adopt a phased approach to the fall semester, which we believe will best safeguard the health and safety of our University community and our Charlottesville neighbors and give us the best chance of a successful return to Grounds,” U-Va. President James E. Ryan and other university officials wrote in a letter to the school community.

“We still plan to welcome all students back to Grounds, but out of caution, we will do it a bit more slowly than originally intended.”

The public university last fall had about 25,000 students, including 17,000 undergraduates.

U-Va. officials said plans for delivery of graduate and professional courses remain unchanged.

Face-to-face teaching of undergraduates will begin on Sept. 8, the university said, and students will be able to move back to the campus in the days before then.

Campus conditions are expected to be tightly regimented, with students required to wear face masks in closed public spaces, maintain social distance and use assigned sinks and showers.

Those who live on campus will be assigned to double rooms, as usual, officials have said, and they will be allowed to choose roommates in advance.