Pope Leo XIV has called on the Catholic Church to heal "deep wounds" and "painful errors" ahead of a private meeting with survivors of child sexual abuse during his four-day visit to France.

Addressing an estimated crowd of 150,000 people in a large field near the Catholic shrine of Lourdes on Sunday, the first US pope called on the Church to reckon with its past, without directly referencing sexual abuse scandals in France that affected at least 330,000 children over seven decades.

"In order to heal the deep wounds, infidelities and painful errors that have occurred within [the church], we must humbly place ourselves under the Lord's purifying gaze," he said.

Leo met French bishops earlier on Sunday, telling them they had acted with determination against "the painful scourge of abuse committed against minors by members of the clergy or in an ecclesial context against minors." He urged them "to continue along the path you have begun, maintaining the greatest vigilance," according to a transcript released by the Vatican.

Later on Sunday, the pope was due to privately meet seven survivors of child sexual abuse by French clergy, following an open-air morning mass at Lourdes, one of the most visited Catholic pilgrimage sites in the world and reputed as a place of healing.

Arriving at Lourdes in a white popemobile on Saturday night, Leo passed boarded-up mosaics created by a Jesuit priest accused of abusing more than two dozen women over three decades. Marko Rupnik, one of the Catholic Church's best-known mosaic artists, is on trial in a Vatican court, accused by more than two dozen women of having psychologically, spiritually and sexually abused them from the 1990s, including during the creation of his artworks. Rupnik is not known to have commented publicly on the allegations. The bishop of Lourdes ordered the works covered up, reasoning that survivors seeking solace at the site should not be forced to see them.

Among the survivors scheduled to meet the pope is a former pupil of the nearby Catholic boarding school Notre-Dame de Betharram, whose former students have recounted experiences of violence, rape and sexual assault in what is considered the largest child sexual abuse scandal at a school in French history.

In an interview published last year, Leo spoke of the "crisis" of clerical sexual abuse in the Church. He also said "victims must be treated with great respect and with an understanding that those who have suffered very deep wounds because of abuse, sometimes carry those wounds for their entire life," according to a transcript on the Holy See's official news site.

The papal visit, the first to France in 18 years, follows an announcement last week by the country's Independent National Authority for Recognition and Reparation that approximately 2,000 people who reported sexual abuse by clergy or other Church representatives were seeking reparations.

France's Catholic bishops conference agreed to provide compensation following a landmark report in 2021, which estimated that 330,000 children were sexually abused over seven decades by predatory priests or other Catholic figures. The two-and-a-half-year independent inquiry found that vast numbers of children were subjected to sexual violence and that the crimes were covered up in a "systemic way" by a deliberate "veil of silence" within the Church.

On the day Leo arrived in Paris, a group of survivors published an open letter voicing fears that his visit would change nothing. The letter criticised the fact that the seven survivors selected to meet the pope in Lourdes were "carefully selected" by the Church rather than by survivors' groups.

"You will merely ask us for forgiveness. This is not enough. One does not ask for forgiveness for a crime; one is responsible for a crime," they wrote in the letter, published in the newspaper Liberation.

The pope arrived to celebrate mass on Sunday morning to a rapturous reception from the faithful, who waved flags and cheered as they thronged the streets of Lourdes to catch a glimpse of him.