The Vatican today said that Monsignor Dario Vigano, the Italian head of the Vatican communications department who was caught up in the so-called 'Lettergate' scandal, has resigned.

A brief Vatican statement said Pope Francis had 'accepted' Vigano's resignation but a Vatican source said the prelate had been told to offer it, meaning he was sacked.

Vigano, 55, whose formal title was Prefect of the Secretariat for Communication, had come under sharp criticism for blurring part of a photograph of a letter by the retired Pope Benedict XVI and citing it selectively for a week before releasing the entire text on Saturday.

The episode cast a shadow over the Vatican and was a public relations fiasco, particularly because earlier this year, the pope wrote a document on, and spoke about, the dangers of 'fake news'.

The letter was meant to remain confidential but Vigano read selected passages of it at the presentation on March 12 of a Vatican-published 11-booklet series on the theology of Pope Francis.

The Vatican initially omitted a paragraph in which Benedict apologised for not having had the time to read all 11 volumes and thus declining a request to write a 'short and dense theological' introduction for the series.

The final paragraph, released for the first time on Saturday, went further, showing that Benedict was irritated by the fact that German theologian Peter Hunermann had been chosen by the Vatican publishing house LEV to write one of the volumes.

Additional reporting by Reuters.