Pope Francis has formally changed church teaching about the death penalty, saying it can never be sanctioned because it "attacks" the inherent dignity of all humans, declaring the punishment inadmissible in all circumstances.

The Vatican said Thursday that Francis had changed the Catechism of the Catholic Church — the compilation of official Catholic teaching — to reflect Pope Francis' total opposition to the death penalty. Previously, the catechism said the church didn't exclude recourse to capital punishment "if this is the only possible way of effectively defending human lives against the unjust aggressor."

The new teaching, contained in Catechism No. 2267, says the previous policy is outdated, that there are other ways to protect the common good, and that the church should instead commit itself to working to end capital punishment.

"The church teaches, in the light of the Gospel, that the death penalty is inadmissible because it is an attack on the inviolability and dignity of the person and she works with determination for its abolition worldwide," reads the new text, which was approved in May but only published Thursday.

The death penalty has been abolished in most of Europe and South America, but it is still in use in the United States and in several countries in Asia, Africa and the Mideast. In addition, just this week Turkish President Tayyip Erdogan said Turkey could soon move to reinstate the death penalty, which it had abolished in 2004 as part of its bid to join the European Union.

In an accompanying letter explaining the change, the head of the Vatican's doctrine office said the development of Catholic doctrine on capital punishment didn't contradict prior teaching but rather was an evolution of it.

"If, in fact the political and social situation of the past made the death penalty an acceptable means for the protection of the common good, today the increasing understanding that the dignity of a person is not lost even after committing the most serious crimes," said Cardinal Luis Ladaria, prefect of the Congregation for the Doctrine of the Faith.

Ladaria said the new change aims to "give energy" to the anti-death penalty movement "and, in respectful dialogue with civil authorities, to encourage the creation of conditions that allow for the elimination of the death penalty where it is still in effect."

Francis has long railed against the death penalty, insisting it can never be justified, no matter how heinous the crime. He has also long made prison ministry a mainstay of his vocation. On nearly every foreign trip, Francis has visited with inmates to offer words of solidarity and hope, and he still stays in touch with a group of Argentine inmates he ministered to during his years as archbishop of Buenos Aires.

He announced his intention to change church teaching on capital punishment last October, when he marked the 25th anniversary of the publication of the catechism by announcing his intention to update it. The catechism, first promulgated by St. John Paul II, gives Catholics an easy, go-to guide for church teaching on everything from the sacraments to sex.

At that 2017 ceremony, Francis said the death penalty violates the Gospel and amounts to the voluntary killing of a human life, which "is always sacred in the eyes of the creator."

He acknowledged that in the past even the Papal States had allowed this "extreme and inhuman recourse." But he said the Holy See had erred in allowing a mentality that was "more legalistic than Christian" and now knew better.

Amnesty International, which has long campaigned for a worldwide ban on the death penalty, welcomed the development as an "important step forward."

"Already in the past, the church had expressed its aversion to the death penalty, but with words that did not exclude ambiguities," said Riccardo Noury, Amnesty Italia spokesman. "Today they are saying it in an even clearer way."

In addition, he praised the clear indication of the church's commitment to the cause beyond doctrine.

"There seems to be also a desire to see the Catholic Church take an active role in the global abolitionist movement," he added.