A landmark ruling approved by Pope Francis says priests can bless same-sex couples under some circumstances.

A document from the Vatican’s doctrinal office approved by Pope Francis on Monday said such blessings would not legitimise irregular situations but be a sign that God welcomes all.

The document backed “the possibility of blessings for couples in irregular situations and for couples of the same sex” but “this blessing should never be imparted in concurrence with the ceremonies of a civil union, and not even in connection with them”.

It said priests should decide on a case-by-case basis and “should not prevent or prohibit the Church’s closeness to people in every situation in which they might seek God’s help through a simple blessing”.

The document elaborates on a letter Francis sent to two conservative cardinals that was published in October. In that preliminary response, Francis suggested such blessings could be offered under some circumstances if they didn’t confuse the ritual with the sacrament of marriage.

The new document repeats that rationale and elaborates on it, reaffirming that marriage is a lifelong sacrament between a man and a woman. It stresses that blessings should not be conferred at the same time as a civil union, using set rituals or even with the clothing and gestures that belong in a wedding.

But it says requests for such blessings should not be denied full stop. It offers an extensive definition of the term “blessing” in Scripture to insist that people seeking a transcendent relationship with God and looking for his love and mercy should not be subject to “an exhaustive moral analysis” as a precondition for receiving it.

“Ultimately, a blessing offers people a means to increase their trust in God,” the document said. “The request for a blessing, thus, expresses and nurtures openness to the transcendence, mercy, and closeness to God in a thousand concrete circumstances of life, which is no small thing in the world in which we live.”

The Vatican holds that marriage is an indissoluble union between man and woman. As a result, it has long opposed same-sex marriage.

And in 2021, the Vatican’s Congregation for the Doctrine of the Faith said flat-out that the church couldn’t bless the unions of two men or two women because “God cannot bless sin”.

That document created an outcry, one it appeared even Francis was blindsided by, even though he had technically approved its publication. Soon after it was published, he removed the official responsible for it and set about laying the groundwork for a reversal.

It stressed that people in “irregular” unions – gay or straight – are in a state of sin. But it said that shouldn’t deprive them of God’s love or mercy.

Pope Francis has recently criticised laws that criminalise homosexuality as “unjust”, saying God loves all his children just as they are and calling on Catholic bishops who support the laws to welcome LGBTQ people into the church.

The Vatican in 2008 declined to sign onto a UN declaration that called for the decriminalisation of homosexuality, complaining the text went beyond the original scope and also included language about “sexual orientation” and “gender identity” it found problematic.