ROME — The Vatican said on Monday that priests could not bless same-sex unions, calling any such blessing “not licit.”

The Congregation for the Doctrine of the Faith, the Vatican’s doctrinal watchdog, issued the judgment in response to questions raised by some pastors and parishes that sought to be more welcoming and inclusive of gay couples.

In an explicatory note signed by the prefect of the Congregation, Cardinal Luis F. Ladaria, the congregation said that Pope Francis had “given his consent to the decision.”

The ruling said that the church should be welcoming toward gay people, but not their unions. Catholic teaching holds that marriage between a man and woman is part of God’s plan, and since gay unions are not intended to be part of that plan, they cannot be blessed by the church.

The issue had emerged more forcefully in recent years in response to Pope Francis’ request of bishops following meetings on the family to develop projects and pastoral proposals “so that those who manifest a homosexual orientation can receive the assistance they need to understand and fully carry out God’s will in their lives.”

Blessings of same-sex unions had been advanced as one sign of inclusiveness, and the Vatican said in its note that such projects were often “motivated by a sincere desire to welcome and accompany homosexual persons,” and help them to grow in faith.

Francis has said that gay couples should have legal protection, but only in the civil sphere, and he has continued to oppose gay marriage.