DUBLIN — A former Vatican ambassador to the United States has alleged in an 11-page letter that Pope Benedict XVI and Pope Francis – among other top Catholic Church officials – had been aware of sexual misconduct allegations against former Washington, D.C., archbishop Cardinal Theodore McCarrick years before he resigned this summer.

The letter from Archbishop Carlo Maria Vigano, who was recalled from his D.C. post in 2016 amid allegations that he’d become embroiled in the conservative American fight against same-sex marriage, was first reported by the National Catholic Register and LifeSite News, two conservative Catholic sites.

The letter offered no proof, and Vigano on Sunday told The Washington Post he wouldn’t comment further.

“Silence and prayer are the only things that are befitting,” he said.

The accusations landed as Francis was wrapping up one of the most fraught trips of his papacy, coming face-to-face with the church’s damaged credibility in Ireland, a country reeling from decades of abuse.

In a Mass at Dublin’s Phoenix Park, Francis spoke in Spanish and asked for forgiveness for what he called “abuses of power, conscience, and sexual abuse perpetrated by members with roles of responsibility in the church,” according to a translation of his remarks by Vatican News.

“We ask forgiveness for some members of the church’s hierarchy who did not take charge of these painful situations and kept quiet,” Francis said.