Geneva -- Swiss Roman Catholic bishops on Tuesday condemned Holocaust denial and warned four leading traditionalists they must openly welcome Judaism to be fully reconciled with Rome.

The statement by the Swiss bishops conference came days after the Vatican lifted the excommunication of the four traditionalist bishops, prompting dismay in the Jewish community especially following remarks by Roger Williamson, a British prelate.

Just before the move by Pope Benedict XVI last week, Williamson gave an interview to Swedish television in which he cast doubt on the use of the gas chambers by the Nazis and the death toll in the Holocaust, sparking outrage and an investigation by German prosecutors.

In a statement on Tuesday, the Swiss bishops conference warned it could not tolerate Holocaust denial and called on the four, who belong to a Swiss-based traditionalist community, to "adopt a positive attitude towards Judaism."

They underlined that the rebel 'bishops' remained suspended even though their excommunication was lifted.

The Swiss bishops also "asked the Jewish communities of Switzerland to excuse the irritations that have happened in recent days."

The lifting of the excommunication only marked the beginning of dialogue with the traditionalist leaders, according to the conference.

"In view of the deep differences, the road could be long," it added, acknowledging that Williamson's remarks added to their doubts.

Bernard Fellay, the head of the traditionalist Priestly Society of Saint Pius X, and one of the four, has distanced the community from Williamson's comments.

He apologised to Pope Benedict XVI and those of "good faith" following Williamson's remarks, in a statement released by the Vatican on Tuesday.

"The declarations of Monsignor Williamson do not reflect in any way the position of our society. That is why I forbade him, until new order, from taking any public stances on political or historical questions," he said.

"We ask forgiveness to the Sovereign Pontiff and all the men of good will for the dramatic consequences of such an act," the statement said.

But the Swiss bishops conference pointed out that one of the cornerstones of the 20-year schism with the arch-conservative group was their refusal to accept ecumenism and the Vatican's statement of reconciliation in 1965 with non-Christian faiths.

That stance must be reversed by the traditionalists in a "credible" declaration during talks with the Roman Catholic Church on full rehabilitation, they added.

The Vatican on Saturday published an edict lifting the 1998 sanction on Williamson, Fellay and two other bishops in his breakaway conservative movement, Bernard de Tissier de Mallerais and Alfonso de Gallerata.

AFP/Expatica