Rome — Citing the need to protect the “prestige” of Italy’s university system, the country’s higher-education minister, Fabio Mussi, ordered its 66 public universities on Wednesday to stop granting honorary degrees for the rest of the year.

The move followed last week’s controversy over the University of Turin’s decision to award an honorary bachelor’s degree in economics to Jonella Ligresti, 40, who is chairwoman of one of Italy’s largest insurance companies, a family business, but who was previously known as a medal winner in equestrian events. The university acted over the objections of Mr. Mussi, who by law must sign off on all such degrees before they can be granted.

Honorary diplomas are awarded more rarely in Italy than in the United States, and are reserved by law to those who “by their deeds or publications have achieved manifest fame of singular skill in the discipline for which the degree is granted.”

In recent years, Italian universities have honored an increasing number of celebrities with debatable academic achievements, including the champion motorcycle racer Valentino Rossi, who in 2005 received an honorary bachelor’s degree in communication and advertising from the University of Urbino. The trend prompted Mr. Mussi last fall to urge institutions to make “an accurate evaluation” of those they would honor in this way. —Francis X. Rocca