Pope Francis expressed "pain and shame" over the Catholic Church's failure to deal with abuse and met with eight victims during a visit to Ireland on Saturday where the prime minister pressed him to take action.
Francis said the "failure of ecclesiastical authorities... adequately to address these repellent crimes has rightly given rise to outrage, and remains a source of pain and shame for the Catholic community.
"I myself share those sentiments," he said in a speech in Dublin Castle, speaking alongside Irish Prime Minister Leo Varadkar.
The pope later held an hour and a half meeting with victims of abuse at the hands of clergy or in Church-run institutions, including Marie Collins, who was, at the age of 13, abused by a priest while being treated in a hospital in Dublin.
Collins, who last year resigned from a Vatican commission for child protection over its inaction, told reporters that the pope's speech was "disappointing" and "nothing new".
One of the victims of Fr Tony Walsh, a priest and serial abuser who assaulted hundreds of children over nearly two decades, was also present but preferred to remain anonymous.
- 'Cries for help' -
Paul Jude Redmond, who was adopted illegally from a Catholic-run home in the 1960s where his mother had been interned for being pregnant and unmarried, was among those who met the pope.
Redmond said the pope "lifted his hands to his head in shock" during the closed-door meeting after hearing stories of ill-treatment in Church-run Mother and Baby Homes.
"We feel hopeful there will be more movement from the Church," Redmond said in a statement put out by the Coalition of Mother and Baby Home Survivors.
Varadkar, an openly gay leader and a symbol of Ireland's liberalising culture, demanded from Pope Francis "that from words flow actions" for victims in a strongly-worded speech.
He said Ireland's multiple historic scandals were "stains on our state, our society and also the Church."
"Far too often there was judgement, severity and cruelty... people kept in dark corners, behind closed doors, cries for help that went unheard," he added.
"There is much to be done to bring about justice and truth and healing for victims and survivors. Holy Father, I ask that you use your office and influence to ensure that this is done here in Ireland and across the world."
- 'An inspirational man' -
Francis's visit was the first by a pope in this former bastion of Catholicism since John Paul II spoke to a crowd of 1.5 million people during a visit in 1979.
Irish society is virtually unrecognisable from that time.
A new generation has shed Ireland's traditional mores, electing Ireland's first gay prime minister and voting to legalise same-sex marriage and abortion -- both once unthinkable.
In Dublin, tens of thousands of people lined the streets to cheer Pope Francis on as his Popemobile made its way from St Mary's Pro-Cathedral, where he gave marriage advice to couples, to a hostel for homeless families.
"I just think he is an inspirational man. He has a difficult job to do to try and bring around a lot of changes in the Church but he is doing his best I feel," said Eileen Grier-Gavin, who came from County Mayo in western Ireland to see the pope pass by.
The pope later attended a Festival of Families in Croke Park Stadium with more than 82,000 people in attendance.
- 'Still in denial' -
Earlier this month, the Vatican was rocked by a devastating US report accused more than 300 priests in Pennsylvania state of abusing more than 1,000 children since the 1950s.
The pope wrote a letter to the world's 1.3 billion Catholics vowing to prevent future "atrocities" but also conceding that no efforts "to repair the harm done will ever be sufficient".
Ireland has grappled with its own history of abuse, with multiple probes finding Church leaders protected hundreds of predatory priests over the decades.
The Argentine pontiff was in Ireland to close the 2018 World Meeting of Families (WMOF) -- a global Catholic gathering that takes place every three years.
The highlight of the trip will be an outdoor mass in the city's Phoenix Park on Sunday, which is expected to draw 500,000 people.
Priests and nuns from across Ireland have flocked to the capital, although merchandise sellers said business was sluggish.
"Local people are not spending," said street vendor Tony Mooney, 67. "There's an awful lot of not nice things being said to us."
Richard Duffy, 31, said he was opposed to the visit, telling AFP "it just boggles my mind that there's a celebration for him coming here."
"They're still in denial and refusing to admit any fault," he added.