The Vatican says the recent ordinations of 20 priests by a conservative, traditionalist Roman Catholic group are illegitimate since it has no legal status within the church.
Over the past two weeks, the Society of St. Pius X ordained the priests in ceremonies in the United States, Switzerland and Germany.
Vatican spokesman the Rev. Federico Lombardi said Tuesday the ordinations are considered illegitimate.
The group opposes the reforms of Vatican II. In 1988, the Vatican excommunicated its founder and four of his bishops after he consecrated them without papal consent.
In a 2009 bid to reconcile with the group, Benedict lifted the excommunication of the bishops. Protests ensued because one had denied the extent of the Holocaust.