The Vatican has expressed "shame and sorrow" over a scathing Pennsylvania grand jury report about clergy who raped and molested children in six dioceses in the state.
The abuse was "criminally and morally reprehensible", the Vatican said, and added Pope Francis wanted to eradicate "this tragic horror".
Harrowing examples of horrendous abuse filled the long-awaited report.
In one such example, a young girl was raped by a priest visiting her while she was in a hospital following surgery to remove her tonsils.
In another, a priest tied up a victim with a rope in a confessional booth, and when the victim refused to perform sex, the priest assaulted him with a crucifix.
A written statement using uncharacteristically strong language for the Holy See, Vatican spokesman Greg Burke sought to assure victims that "the pope is on their side."
Mr Burke said the incidents of abuse graphically documented in the report were "betrayals of trust that robbed survivors of their dignity and their faith."
"The church must learn hard lessons from its past, and there should be accountability for both abusers and those who permitted abuse to occur," he said.
Pope Francis himself wasn't quoted in the statement, and there was no mention of demands in the United States among some Roman Catholics for the resignation of Cardinal Donald Wuerl.
Cardinal Wuerl was accused in the report of helping to protect some molester priests while he was bishop of Pittsburgh, Pennsylvania.
He defended his actions in Pittsburgh while apologising for the damage inflicted on victims.
"The Diocese worked to meet or exceed the requirements of the United States Conference of Catholic Bishops and the reporting requirements of Pennsylvania law," Wuerl said, according to the Associated Press.
"We showed pastoral concern by reaching out to victims and their families, while reporting allegations to the authorities so they could investigate crimes."
Victims and their advocates for decades have lamented that top Catholic churchmen repeatedly put the reputation of the church ahead of obligations to protect children from harm from paedophile priests.
In a sign that Pope Francis wants to end that pervasive mind set among church hierarchy, including bishops and cardinals, he recently accepted the resignation from cardinal's rank of former Washington archbishop Theodore McCarrick amid allegations that the American prelate had engaged in sexual misconduct.
Resignations by cardinals are extremely rare, and McCarrick's was the first time a prelate lost his cardinal's rank in a sexual abuse scandal.
Burke said Pope Francis "understands well how much these crimes can shake the faith and the spirit of believers and reiterates the call to make every effort to create a safe environment for minors and vulnerable adults in the church and in all of society."
The grand jury report documented how paedophile priests were often protected by church hierarchy or moved to other postings without the faithful being told of the priests' sexual predatory history.
Speaking about Pope Francis, Burke said: "Those who have suffered are his priority, and the church wants to listen to them to root out this tragic horror that destroys the lives of the innocent."
Even before the report was released, a series of scandals over the last few decades involving paedophile priests and systematic attempts by pastors and bishops to cover up the abuse by shuttling offenders to new parishes had rocked the faith of many Catholics in the US.
Similar abuse and determination by protect abusers had also stained the reputation of the Catholic Church in many other countries.
Pope Francis recently did a turnaround on how accusations by victims in Chile were viewed by the Vatican.
After casting doubt on the victims' accounts during his visit to Chile earlier this year, Pope Francis apologised to them, hosted the victims at the Vatican and later accepted the resignations of some of the country's bishops, who offered en masse to step down.
On Thursday, the US Conference of Catholic Bishops invited the Vatican to play a key role in investigating the scandal involving McCarrick, who allegedly engaged in sexual misconduct with minors and adult seminarians.
The conference's president, Cardinal Daniel DiNardo of Galveston-Houston, said he would go to Rome to ask the Vatican to conduct a high-level investigation known as an "apostolic visitation" to deal with McCarrick's case, working together with a group of predominantly lay experts.