In the 1950s, Mohammed Reza Pahlavi, Shah of Iran, then divorced from his second wife, indicated his interest in marrying Princess Maria Gabriella.

Pope John XXIII reportedly vetoed the suggestion. In an editorial about the rumors surrounding the marriage of "a Muslim sovereign and a Catholic princess", the Vatican newspaper, L'Osservatore Romano, considered the match "a grave danger," especially considering that under the 1917 Code of Canon Law a Roman Catholic who attempted to contract a marriage with a divorced person could incur the penalty of excommunication.