Pope Benedict is still due to visit to Israel in May, an Israeli official said on Sunday, despite angering Jews worldwide by re-admitting a bishop who has denied the full extent of the Nazi genocide of six million Jews.

The Yad Vashem Holocaust Museum and Memorial in Jerusalem decried as "scandalous" Benedict's decision to lift excommunications on British-born bishop, Richard Williamson, who has said there were no gas chambers and only 300,000 Jews perished in Nazi concentration camps in World War Two.

Foreign Ministry spokesman Yigal Palmor, said, however, the pontiff's planned visit in May to Israel was not in doubt. "This has nothing to do with relations between states," he said.

The Israeli museum's fury marked another step in the row between the Catholic Church and world Jewish groups, who were outraged by announcements of the rehabilitation.

"The reinstatement is an internal Church matter...[however] denial of the Holocaust not only insults the survivors, memory of the victims, and the Righteous Among the Nations who risked their lives to rescue Jews, it is a brutal attack on truth," Yad Vashem said in a statement.

A senior official in the Jewish Agency on Sunday also slammed the decisions, calling it a "scandal."

"It is something we cannot understand," said Amos Hermon, head of the Task Force Against Anti-Semitism at the quasi-governmental Jewish Agency.

Bishop Williamson was one of four traditionalist bishops to have his excommunication lifted Saturday, just days after he was shown in a Swedish state TV interview saying that historical evidence is hugely against six million Jews having been deliberately gassed by the Nazis during the Holocaust.

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.

"Even if the revocation of the excommunication is unrelated to Williamson's comments regarding the Holocaust, what kind of message is this sending regarding the Church's attitude toward the Holocaust?" Yad Vashem wrote. "Although we understand that Williamson's statements do not represent the Church's stance, we continue to hope that the Church will vigorously condemn these unacceptable and odious comments."

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 late last week.

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.