"It is difficult to have a dialogue when one side is missing," the Rev. Remi Hoeckman, secretary of the Vatican's office for relations with Jews, said Friday. "We hope to hold it at a later date."
The symposium was a Holy Year event and was to include speeches by three cardinals and two Italian rabbis: Elio Toaff, chief rabbi of Rome, and Abramo Piattelli.
"Rabbi Toaff and I wrote a letter to the organizers telling them that in the climate created after the views expressed by Cardinal [Joseph] Ratzinger, we could no longer take part in such an event," Piattelli told The Associated Press.
Piattelli was referring to a Vatican document issued earlier this month that reasserted the Roman Catholic church's primacy over other Christian denominations and said followers of other religions were in a "gravely deficient situation" regarding salvation.
Some have seen the document as contradicting efforts by Pope John Paul II throughout his papacy to reach out to non-Catholics.
The Vatican said the document was issued because some theologians have been hindering the church's missionary efforts by manipulating fundamental truths to depict all religions as equal.
Toaff, the chief rabbi of Rome, has over the years struck up a warm relationship with John Paul after welcoming him to Rome's main synagogue in 1986--a first-ever visit by a pope to a Jewish house of worship.
John Paul also prayed at the Western Wall in Jerusalem during his visit to the Holy Land in March.