Father Floriano Abrahamowicz was quoted as saying that he did not know if anyone had died in Nazi gas chambers.
The reports were carried by Italian newspaper La Tribuna di Treviso, and the AP news agency said Fr Abrahamowicz had confirmed their accuracy.
Last week a bishop, whose expulsion was lifted last week by the Pope, sparked a row by questioning the Holocaust.
Richard Williamson is one of four bishops, who are members of the Society of Pius X, whose excommunication was lifted last week by the Pope.
He outraged Jewish leaders when he said he believed there had been no Nazi gas chambers.
The leader of the group has since said that the views "do not reflect in any way the position of the society".
The Vatican says it was unaware of Bishop Williamson's views on the Holocaust when the decision was made to readmit the group.
'No gas chambers'
The bishop angered Jewish leaders across the world when he told Swedish TV: "I believe there were no gas chambers. I think that 2-300,000 Jews perished in Nazi concentration camps but none of them by gas chambers."
Pope Benedict quickly distanced himself from the comments and expressed "full and indisputable solidarity" with Jews.
However, condemnation from Jewish groups was widespread and the Chief Rabbinate of Israel broke off official ties with the Vatican in protest over the Pope's decision to rehabilitate the bishop.
Then Father Abrahamowicz expressed his own doubts about the Holocaust in an interview published on Thursday by Tribuna di Treviso.
"I know gas chambers existed at least to disinfect, I can't say if anybody was killed in them or not," he said.
On Thursday, Bishop Bernard Fellay, superior general of the Society of St Pius X, asked for forgiveness from the Pope for the "dramatic consequences" of Bishop Williamson's comments.
Bishop Fellay said he had forbidden Bishop Williamson from speaking publicly about any historical or political questions and that his views "don't reflect in any way the position of the society".
He also referred to the "genocide of Jews" by the Nazis.
'No-one knew'
The cardinal who led negotiations with the society was quoted as saying that no-one at the Vatican knew about Bishop Williamson's views until after the decree lifting the excommunication had been signed.
"We absolutely didn't know anything about this… I really think that no-one was aware of it," Cardinal Dario Castrillon Hoyos said in an interview with Corriere della Sera.
