Vatican investigates usage of Franciscus papal account after it 'liked' a racy picture on Instagram.

The Vatican has launched an investigation into how Pope Francis’ official Instagram account 'liked' a sexy photo of a scantily-clad Brazilian model, reports the Catholic News Agency (CNA).

An internal probe is underway into usage of the verified papal Instagram account, Franciscus, which is managed by a social media team and not the pontiff himself.

Franciscus 'liked' an Instagram picture of Natalia Garibotto standing at a school locker and wearing a lingerie outfit in the style of a school uniform.

Before Franciscus unliked the image, the 27-year-old model claimed to have received the papal seal of approval, joking to her followers: "At least I’m going to heaven."