A preliminary report written by bishops during a Vatican synod said homosexuals had “gifts and qualities to offer”.
The report does not challenge the Church’s long-held opposition to same-sex marriage, but some gay rights groups hailed it as a breakthrough.
Conservative groups rejected the report, one labelling it a “betrayal”.
More than 200 bishops have been taking part in the synod since 5 October. It was convened by Pope Francis to debate controversial issues such as abortion, contraception, homosexuality and divorce.
Monday’s report, issued half-way through the two-week meeting, said: “Homosexuals have gifts and qualities to offer to the Christian community.
“Are we capable of welcoming these people, guaranteeing to them a fraternal space in our communities?”
Breakthrough or betrayal?
The document adds: “Without denying the moral problems connected to homosexual unions, it has to be noted that there are cases in which mutual aid to the point of sacrifice constitutes a precious support in the life of the partners.”
Human Rights Campaign, a leading US gay rights organisation, said the document set a “dramatic new tone”.
The London-based Catholic gay rights groups Quest called parts of it a “breakthrough”.
However Voice Of The Family, a conservative Roman Catholic organisation, rejected the interim report as a “betrayal”.
The group’s co-founder John Smeaton called it “one of the worst official documents drafted in Church history”.
Last year, a survey launched by Pope Francis suggested that the majority of Catholics rejected Church teaching on issues such as sex and contraception.