The Catholic Church is to end its relationship with an adoption service following changes in legislation.
In 2012 a judge ruled that unmarried and same-sex couples should be allowed to adopt.
The Catholic Bishops of Northern Ireland said it was "with regret" that they were ending their relationship with The Family Care Society NI.
The DUP have said the decision shows the need for a conscience clause for religious groups in legislation.
The Family Care Society NI was founded by the church and has offices in the Derry Diocesan Pastoral Centre and Down and Connor Good Shepherd Centre on the Ormeau Road in Belfast.
In a statement on Friday, the society said: "Providing vital adoption and support services needed by children and families has always been our focus and will remain so.
"We look forward to continuing a dialogue with the Northern Bishops over the coming months about the decision they have found it necessary to take; support from the Bishops has greatly assisted FCS in the past, particularly in providing services to adults who were adopted, fostered or raised in a Catholic children's home.
"Any funds they make available will continue to be used only for purposes consistent with the Church's doctrine and ethos."
The bishops said it was "unreasonable for legislators to oblige faith based organisations to act against their fundamental and reasonable religious beliefs in the provision of services that contribute to the common good".
"As a result the Family Care Society is now legally obliged to receive and process applications in accordance with the new and wider interpretation of adoption law established by the High Court decision.
"Since the provision of adoption services in Northern Ireland now also involves acting against the Church's teaching and ethos, we too have no option but to end the long established relationship between the Church and The Family Care Society NI.
"The law now makes it impossible for this agency to continue with the support it has enjoyed up to now from the Church."
The adoption law changed in 2012 after a case taken by the Human Rights Commission.
Previous Health Minister Edwin Poots challenged that decision in the Court of Appeal but it ruled that legislation which prevents civil partners adopting was unlawful.
Mr Poots then tried to appeal to the Supreme Court which said there were no grounds for an appeal and dismissed it.
The DUP MLA Paul Givan said he was "deeply disappointed" that the church had ended its relationship with the adoption provider and said that such a circumstance demonstrates the need for a conscience clause in Northern Ireland.
"This decision by the Catholic Church is another reminder that our laws do not make provision for those with perfectly legitimate religious beliefs," he said.
"Equality of opportunity for Catholics to access adoption services from their own church is being denied as a result of our laws.
"Just as with Ashers Bakery, the Catholic Church should not have to act in violation of its deeply held religious beliefs. A truly tolerant society should be capable of making space to accommodate difference in our community."