Pope Francis has asked for forgiveness for all Christians who buy sex from women.

The 81-year-old pontiff described men who frequent prostitutes as criminals with a “sick mentality” who think women exist to be exploited.

“This isn’t making love. This is torturing a woman. Let’s not confuse the terms,” he said.

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The Pope made the comments during a four-hour listening session with 300 young people invited by the Vatican to Rome to help leaders learn what children think about the Catholic Church.

Blessing Okoedion, from Nigeria, asked the Pope how the church could allow Catholics to buy sex from the many Nigerian women in Italy who are forced to be sex slaves by their traffickers.

“I ask myself, and I ask you: Is the male chauvinistic church able to truthfully ask itself about this high demand by clients?” she asked.

The pontiff, who has made the fight against human trafficking and modern-day sex slaves a priority since taking office, urged young people to take up the fight against trafficking and forced prostitution.

“This is one of the battles that I ask you young people to do, for the dignity of women,” he said.

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He said forced prostitution was born of a “sick mentality” which no form of feminism has managed to rid from society, one that thinks “women are to be exploited”.

Speaking to Ms Okoedion, who was forced into prostitution but managed to escape it, the Pope concluded: “I want to take advantage of this moment, because you talked about baptised and Christians, to ask your forgiveness, from society and all the Catholics who do this criminal act.”