Pope Francis has said that he thinks same-sex couples should be allowed to have "civil unions".
He made the comments, which observers say are his clearest remarks yet on gay relationships, in a documentary directed by Evgeny Afineevsky.
"Homosexual people have a right to be in a family," he said in the film, which premiered on Wednesday.
"They are children of God and have a right to a family. Nobody should be thrown out or made miserable over it.
"What we have to create is a civil union law. That way they are legally covered."
He added that he "stood up for that", apparently referring to his time as Archbishop of Buenos Aires when, although opposing same-sex marriages in law, he supported some legal protections for same-sex couples.
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The film Francesco, about the life and work of Pope Francis, premiered as part of the Rome Film Festival.
As well as the Pope s comments on civil unions, the film also shows him encouraging two gay men to attend church with their three children.
Pope Francis s biographer, Austen Ivereigh, told the BBC he was "not surprised" by the latest comments.
"This was his position as Archbishop of Buenos Aires," said Mr Ivereigh. "He was always opposed to marriage being for same-sex couples. But he believed the church should advocate for a civil union law for gay couples to give them legal protection."
Under current Catholic doctrine, gay relationships are referred to as "deviant behaviour".
In 2003, the Vatican s doctrinal body, the Congregation for the Doctrine of the Faith, said that "respect for homosexual persons cannot lead in any way to approval of homosexual behaviour or to legal recognition of homosexual unions".
Strong words but no sign of doctrinal change
The remarks have set tongues wagging among Vatican-watchers - and they mark Francis s clearest support for the issue since becoming Pope.
But is this really a fundamental change by the pontiff - or more an off-the-cuff statement by a leader of the Catholic Church who has been known to flirt with liberal sentiments in the past, only to fall back on traditional doctrine when push comes to shove?
As archbishop of Buenos Aires before becoming Pope, he was a staunch opponent of gay marriage, which was legalised in Argentina in 2010, and instead advocated civil unions for homosexual couples.
This is his first vocal backing as Pope - and will undoubtedly be welcomed by many on the more liberal wing of the church and criticised by the conservatives.
But any significant doctrinal change on such an issue would typically be presented in a more formal way and after much internal debate. There is, for now, little sign that either is imminent.
Presentational grey line
What has he said about homosexuality in the past?
The Pope s comments are the latest in a series of sentiments he s expressed about LGBT rights - voicing some support, but not a full endorsement.
In 2013, in the book On Heaven and Earth, the Pope said that legally equating same-sex relationships to heterosexual marriages would be "an anthropological regression".
He also said then that if same-sex couples were allowed to adopt, "there could be affected children... every person needs a male father and a female mother that can help them shape their identity".
That same year, he reaffirmed the Church s position that homosexual acts were sin, but said homosexual orientation was not.
"If a person is gay and seeks God and has good will, who am I to judge?" he asked.
In 2014 it was reported that Pope Francis had expressed support for civil unions for same-sex partners in an interview, but the Holy See s press office denied this.
Then in 2018, Pope Francis said he was "worried" about homosexuality in the clergy, and that it was "a serious matter".