KNOCK, Ireland — The Vatican’s former ambassador to the United States has purportedly written an explosive letter claiming that Pope Francis knew about sex abuse allegations against disgraced ex-Cardinal Theodore McCarrick for years, but chose to cover for him and elevate his position within the church before accepting his resignation last month.
The extraordinary 11-page '"J'accuse," which came as Francis began the second day of a visit to Ireland that has been dominated by the abuse scandal, was published on Sunday by The National Catholic Register and LifeSiteNews and is attributed to Archbishop Carlo Maria Viganò.
NBC News could not confirm the letter's authenticity or its claims.
In it, Viganò said "corruption had reached the very top of the Church's hierarchy" as he called on Francis to resign.
"Pope Francis must be the first to set a good example for cardinals and bishops who covered up McCarrick's abuses and resign along with all of them," he added.
Viganò, who served as ambassador to the United States between 2011 and 2016, claimed that senior Vatican officials knew as early as 2000 that McCarrick regularly invited young seminarians into his bed, but that they still promoted him to cardinal.
Viganò said Pope Benedict XVI eventually imposed sanctions on McCarrick in 2009 or 2010, ordering him to withdraw to a lifetime of prayer and penance, but that Francis chose to rehabilitate him, "cover" for him and elevate him to be a “trusted counselor.”
The letter appeared to be the first public claim that senior church officials not only knew of allegations against McCarrick but quietly sanctioned him long before he was stripped of his public ministry in June.
The Vatican didn't immediately comment on the letter or confirm its authenticity.
In the letter, Viganò wrote that he informed Francis of the allegations against McCarrick soon after he was elected pope in 2013 and alerted him to the sanctions imposed on McCarrick by Benedict.
The former Holy See diplomat added that he was surprised to find that McCarrick, who served as the archbishop of Washington from 2001 to 2006, started travelling on missions on behalf of the church soon after his conversation with Francis.
McCarrick had to retire as archbishop in 2006 when he turned 75, but he became a globe-trotting Vatican emissary after Pope Francis was elected — traveling to international hot spots like Iran and lobbying Washington lawmakers.
This is not the first time that Viganò and Francis have clashed. In 2015, the pair had a dust-up during Francis' visit to the U.S., which Viganò organized.
The allegations came as Francis wrapped-up a highly charged visit to Ireland, where he met with victims of clerical sex abuse as well as other abuses committed by Catholic officials and institutions.
"None of us can fail to be moved by the stories of young people who suffered abuse, were robbed of their innocence," Francis said Sunday during a speech in Knock, west Ireland.
"This open wound challenges us to be firm and decisive in the pursuit of truth and justice," he added. "I beg the Lord’s forgiveness for these sins and for the scandal and betrayal felt by so many others in God’s family."
Sunday was not the first time during the visit that Francis had mentioned the abuse scandal.
Speaking at Dublin Castle on Saturday, Francis said the failure of bishops, religious superiors, priests and others to address these "repugnant" crimes, had "rightly given rise to outrage and remains a source of pain and shame for the Catholic community.”
His words came days after he begged forgiveness and said Catholic leaders were to blame following a grand jury report found that more than 1,000 children had been sexually abused by “predator priests”in Pennsylvania for decades.
"With shame and repentance, we acknowledge as an ecclesial community that we were not where we should have been, that we did not act in a timely manner, realizing the magnitude and the gravity of the damage done to so many lives," Francis wrote in a letter last week.
But neither Francis' words nor a new meeting with abuse victims is likely to calm the outrage among some rank-and-file Catholics following new revelations of sexual misconduct and cover-up in the United States, an ongoing crisis in Chile and prosecutions of top clerics in Australia and France.
McCarrick is one of the highest-ranking Americans to be removed from public ministry because of sex abuse allegations and resigned from the College of Cardinals in the Vatican last month.
Francis accepted his resignation and ordered him to observe a life of prayer and penance in seclusion, sanctions which Viganò said are “similar” to those imposed on him by Benedict years ago.
The Vatican announced in June that McCarrick had been removed from public office after a U.S. church investigation determined that an accusation he had sexually abused a minor was credible.
McCarrick has denied wrongdoing and said he was "shocked" when he learned of the allegation involving a minor some months ago.
As the move was announced, Roman Catholic Church officials in New Jersey revealed that the 88-year-old cardinal had also been accused of sexual misconduct by adults three times in the past. Two of those accusations resulted in secret settlements, officials said.
The accusations, coupled with the Pennsylvania report, have led to a crisis of confidence in the U.S. church.
In the letter published Sunday, Viganò accused the former Vatican secretaries of state under the previous two popes of having ignored detailed denunciations against McCarrick for years.
“Pope Francis has repeatedly asked for total transparency in the Church,” Viganò said.
“He must honestly state when he first learned about the crimes committed by McCarrick, who abused his authority with seminarians and priests.”