The Vatican is looking to develop a new doctrine that calls for excommunicating Catholics for mafia association and corruption.

The decision was reached this week after the Vatican hosted its first-ever conference on fighting corruption and organised crime.

The meeting gathered 50 prosecutors, bishops, victims and UN officials for a day of talks.

In a statement on Saturday, the Vatican said the need had come to develop a new legal doctrine for the Catholic Church about "excommunication for corruption and mafia association".

Pope Francis has long fought against corruption, writing a short book about it as archbishop.

And during a 2014 visit to one of Italy's mafia strongholds, Francis told mobsters they were excommunicated.

But actually developing a doctrine around the concept would mark a new step for the Vatican.