New York University is withholding the diploma of a graduation speaker who delivered an unapproved speech on Wednesday that referred to what he called “the atrocities currently happening in Palestine.”

The move by N.Y.U. to discipline the student speaker, Logan Rozos, is the latest flashpoint between free speech principles and discipline for pro-Palestinian advocacy on American college campuses. It comes as universities across the country brace this commencement season for pro-Palestinian speeches and displays from students and for the anger that pro-Israel voices often express in response.

John Beckman, an N.Y.U. spokesman, said in a statement Wednesday that the university “strongly denounces” Mr. Rozos’ decision to express “his personal and one-sided political views.”

The student “lied about the speech he was going to deliver and violated the commitment he made to comply with our rules,” Mr. Beckman said, adding that the university would withhold his diploma as it pursues disciplinary actions against him. That means that Mr. Rozos would not officially be considered graduated until the matter is resolved.

“N.Y.U. is deeply sorry that the audience was subjected to these remarks and that this moment was stolen by someone who abused a privilege that was conferred upon him,” Mr. Beckman added.

Mr. Rozos, 24, was not immediately available for comment.

Pro-Palestinian activism has diminished on campuses this academic year, in part because of stricter enforcement of disciplinary rules. N.Y.U. has been especially forceful in confronting such activism, including by barring more than two dozen law students from entering some university buildings after they held a sit-in outside of President Linda Mills’s office in March, the student newspaper reported.