A top Vatican official issued a fiery denunciation of allegations that Pope Francis covered up sexual misconduct in the Catholic Church Sunday.

It is a "monstrous" and "even blasphemous" accusation, Cardinal Marc Ouellet wrote in a letter addressed to Archbishop Carlo Maria Vigano. Ouellet was responding to Vigano's accusations that Francis knew about and covered up alleged sex abuse by ex-Cardinal Theodore McCarrick.

Vigano brought forward the allegation against Francis and other high ranking Vatican officials six weeks ago.

McCarrick was barred from publicly continuing his duties in August after Church officials deemed allegations that he sexually abused a minor to be "credible." He has denied the allegations.

Ouellet said in his letter Sunday that there was no evidence to back the cover-up claim against Francis.

He also confirmed for the first time that McCarrick was subject to disciplinary measures. Ouellet specified that the discipline was only an exhortation to live a quiet life of prayer that stopped short of a formal reprobation.

Vigano previously alleged that McCarrick had been sexually active with seminarians and was subsequently disciplined by Pope Benedict XVI. The archbishop claimed that Francis ignored McCarrick's record of sexual misconduct and rehabilitated him to be a powerful member of the church.

Last month, a 2006 letter from a top Vatican official to a New York priest emerged that indicated that the Vatican knew of allegations about McCarrick's sexual misconduct. It is unclear if the pope knew about the letter. 

Francis has refused to confirm or deny Vigano's allegations, saying the letter "speaks for itself" and "I won't say a word about it."

Ouellet defended the Pope Sunday, saying, "Francis had nothing to do with the promotion of McCarrick to New York, Metuchen, Newark or Washington."