A former Vatican ambassador to the United States alleges in a 7,000 word letter that top Catholic Church officials, including Pope Benedict XVI and Pope Francis, were long aware of sexual misconduct allegations against former D.C. archbishop Cardinal Theodore McCarrick.

Last month, McCarrick resigned amid claims he sexually abused seminarians.

The scathing 11-page letter written by Archbishop Carlo Maria Viganò, a conservative critic of Pope Francis who was removed from his position in 2016, came out as Pope Francis was visiting Ireland.

Francis was in Ireland apologizing for abuses by the Catholic Church, including clergy sex abuse and forced adoption of children born to unwed mothers.

In the extensive letter, published in English on the conservative LifeSite News and in Italian on the National Catholic Register, Viganò claims that Benedict knew about former Cardinal McCarrick's behavior sometime in 2009 or 2010 and imposed sanctions on him "with the obligation of dedicating himself to a life of prayer and penance."

Viganò claims he personally informed Pope Francis of Cardinal McCarrick's behavior as early in June 2013. The letter calls on Francis to resign.

"In this extremely dramatic moment for the universal Church," Viganò wrote. "He must acknowledge his mistakes and, in keeping with the proclaimed principle of zero tolerance, 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."

NPR reached out to the Vatican for comment but got no response.

NPR's Sylvia Poggioli reports that Viganò belongs to a conservative faction that blames clerical sex abuse on the presence on homosexuality in the church and believes Pope Francis is too lenient on gay people.

Seventy-seven-year-old Viganò, has previously been controversial.

As NPR reported in 2016, Viganò came under fire for setting up the pope's meeting with controversial Kentucky county clerk Kim Davis in the fall of 2015. Weeks before the meeting, Davis had been put in jail over her refusal to issue marriage licenses to same-sex couples.

According to the New York Times, this is part of the reason why he was removed from his position in the United States by Francis in 2016 and sent back to Rome.

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