VATICAN CITY — Pope Benedict XVI has lifted the excommunications of four traditionalist bishops, including that of a Holocaust denier whose rehabilitation sparked outrage among Jewish groups.
The four bishops were excommunicated 20 years ago after they were consecrated by the late ultraconservative Archbishop Marcel Lefebvre without papal consent _ a move the Vatican said at the time was an act of schism.
The Vatican said Saturday that Benedict rehabilitated the four as part of his efforts to bring Lefebvre's Society of St. Pius X back into the Vatican's fold.
But the move came just days after one of the four, British Bishop Richard Williamson, was shown in a Swedish state TV interview saying that historical evidence "is hugely against 6 million Jews having been deliberately gassed."
WATCH: Interview with Bishop Williamson
Jewish groups denounced the Vatican for having embraced a Holocaust denier and warned that the pope's decision would have serious implications for Catholic-Jewish relations as well as the pontiff's planned visit to the Holy Land later this year.
"I do not see how business can proceed as usual," said Rabbi David Rosen, Jerusalem-based head of interrelgious affairs at the American Jewish Committee and a key Vatican-Jewish negotiator.
He called for the pope or a senior adviser to issue a "clear condemnation" of all Holocaust denials and deniers.
Shimon Samuels of the Simon Wiesenthal Center in Paris said he understood the German-born pope's desire for Christian unity, but said Benedict could have excluded Williamson. He warned that his rehabilitation will have a "political cost" for the Vatican.
"I'm certain as a man who has known the Nazi regime in his own flesh, he understands you have to be very careful and very selective," Samuels said.
The Vatican spokesman, the Rev. Federico Lombardi, said Williamson's views were "absolutely indefensible." But he denied that rehabilitating Williamson implied that the Vatican shared them.
"They are his personal ideas ... that we certainly don't share but they have nothing to do with the issue of the excommunication and the removal of the excommunication," Lombardi told AP Television News.
Williamson's comments cast a cloud over the pope's efforts to normalize relations with the Swiss-based Society of St. Pius X, which Lefebvre founded in 1969. Lefebvre was opposed to the liberalizing reforms of the 1962-65 Second Vatican Council, particularly its ecumenical outreach and its decision to allow Mass to be celebrated in local languages instead of Latin.
Despite concerns from liberal Catholics, Benedict has made clear from the start of his pontificate that he wanted to reintegrate the group back into the Vatican's fold, meeting within months of his election with the current head of the society, Bishop Bernard Fellay.
In 2007, Benedict answered one of Fellay's key demands by relaxing restrictions on celebrating the Latin Mass. In lifting the excommunication decree, he answered the society's second condition for beginning theological discussions about normalizing relations.
The decree from the Vatican's Congregation for Bishops said Benedict "remits" the automatic excommunication that the four bishops incurred and said the 1988 decree declaring their consecrations a schismatic act had no legal standing any longer.
In a statement Saturday, Fellay, who is one of the rehabilitated bishops, expressed his gratitude to Benedict and said the decree would help the whole Roman Catholic Church.
"Thanks to this gesture, Catholics attached to tradition throughout the world will no longer be unjustly stigmatized and condemned for having kept the faith of their fathers," Fellay said in a letter to his supporters.
Fellay, meanwhile, has distanced the society from Williamson's remarks about the Holocaust, saying Williamson only had authority to discuss matters of faith and that he was personally responsible for his own opinions.
But Fellay also berated Swedish state television, accusing it in a Jan. 21 letter of having introduced the Holocaust issue in the interview "with the obvious intention of misrepresenting and maligning," the society.
While Williamson's comments may be offensive and erroneous, they are not an excommunicable offense, said Monsignor Robert Wister, professor of church history at Immaculate Conception School of Theology at Seton Hall University in New Jersey.
"To deny the Holocaust is not a heresy even though it is a lie," he said. "The excommunication can be lifted because he is not a heretic, but he remains a liar."
The Society of St. Pius X, which is based in Menzingen, Switzerland, has six seminaries, three universities and 70 primary and secondary schools around the globe. Aside from the four bishops, it boasts 463 priests and 160 seminarians.
The status of the society's priests remains unsettled. While their ordinations are valid, the Church considers them "illicit" because they were ordained by someone who didn't have the authority, Lombardi said. Pope Paul VI suspended Lefebvre from priestly duties in 1976, but he continued ordaining priests illicitly.
Associated Press Writer Alessandra Rizzo contributed to this report.