Pope Francis has asked for forgiveness for scandals at the Vatican and in Rome, an apparent reference to two cases of priests and gay sex revealed this month during a major meeting of bishops.

"Today ... in the name of the Church, I ask you for forgiveness for the scandals that have occurred recently either in Rome or in the Vatican," Francis said in unprepared remarks during his weekly general audience in St Peter's Square.

"I ask you for forgiveness," he said before tens of thousands of people, who broke into applause. The pope then read his prepared address and did not elaborate.

Asked about the comments, Vatican spokesman Father Federico Lombardi could not say which scandals the pope had in mind but said Francis wanted to reach out to ordinary people who are "disturbed or pained" when they read about scandals caused by "the Church or men of the Church".

There have been two scandals involving the Vatican and the Church in Rome in the past two weeks.

On October 3, a Polish monsignor working in the Vatican's doctrinal office since 2003 held a packed news conference in which he disclosed he was gay and had been living with another man for years.

The Vatican dismissed Monsignor Krzysztof Charamsa, a theologian, from his job there as well as from teaching assignments in pontifical universities in Rome.

The pope also appeared to be referring to a scandal exposed in the Italian media last week about an order of priests who run a parish in a well-to-do neighbourhood in Rome.

Parishioners in the Santa Teresa d'Avila parish wrote to local Church officials alleging a clergyman there had had encounters with "vulnerable adults". Newspapers said these took place in an adjacent park often frequented by male prostitutes.