Speaking on the use of social media, Pope Francis has urged priests and nuns to refrain from watching pornography. 

The pontiff warned that viewing sexually explicit content "weakens the priestly heart".

During the meeting at the Vatican, in which he was asked about his thoughts on social media and the internet, the 86-year-old pope said it wasn't only wrong to watch "criminal pornography like that of child abuse", but also "normal pornography".

"Each of you think if you've had the experience or had the temptation of digital pornography," he said. "It's a vice that so many people have, so many laymen, so many laywomen, and even priests and nuns."

"The pure heart, the heart that receives Jesus every day, cannot receive this pornographic information."

He continued: "I tell you, it is something that weakens the soul. It weakens the soul. The devil enters from there: he weakens the priestly heart."

He offered practical advice to clergy struggling with pornography use, encouraging them to delete explicit apps of their phone "so you won't have the temptation in hand".

Although Pope Francis does not own a phone, he encouraged others to use them to communicate better, instead of viewing pornography.