"We are going to encounter the greatest human catastrophe since World War II," he said.

"I told him that I was incredibly appreciative of the incredible role that he is playing in this planet in discussing issues about the need for an economy based on morality, not greed."

During his 10-minute address, Sanders slammed the current global financial system and praised Francis’ 2015 encyclical on the environment.

"Only God knows what their abductors might have done to them, where they would be by now."

Canadian bishops said the bill was "an affront to human dignity, an erosion of human solidarity and a danger to all vulnerable persons."

"The pope wants to fix the social injustices in society and I am completely with him on that," Sanders told Italian media.