Pope Francis on Wednesday compared abortion to hiring a "hit man to solve a problem", and reiterated his statement about the "depreciation of human life", a point he also made on his visit to Ireland earlier this year.
The remarks, delivered during his weekly audience in St Peter's Square, were unscripted and diverged from his prepared text.
"That's not right, it is wrong to kill a human, regardless of its size, to solve the problem".
Pope Francis said that in his fidelity to his culture and Christian faith, John Paul II sought to "ensure that the Church stood up as the guardian of the inalienable rights of man, of the family and of peoples, in order to be a sign of peace, justice and integral development for the whole human family".
He added: "How can an act that suppresses an innocent and helpless life as it blossoms be therapeutic, civil or, simply, humane?" What do you think?
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The Pope asked if it was right to do away with a human life to "solve a problem".
Many in the crowd shouted "No". He denounced abortion at the time, and likened it to the "white glove" equivalent to Nazi-era eugenics practices.
Shortly after becoming pontiff in 2013, Francis appeared to be cultivating a softer stance towards issues such as abortion and homosexuality, saying that the Catholic church must move on from such arguments and "heal wounds" while focussing instead on "compassion and mercy". That said, Francis has acknowledged that women sometimes are driven by circumstance to abortion and he has extended the ability of ordinary priests - and not just bishops - to absolve them of the sin of abortion if they repent.
Catholic teaching on abortion has been in the headlines lately, including during the divisive confirmation process of US Supreme Court Justice Brett Kavanaugh, a Jesuit-educated Catholic whose vote could overturn legalised abortion in the US.
While Pope Francis has been ambivalent about contraception, his stance on abortion remains adamant.