The mother who left her new-born baby in a New York church's Nativity crib has said that she knew that someone would find him and help him.

Speaking anonymously to the New York Post, she said: "I knew if I left him in God's hands, he would be OK."

The 18-year-old woman, who had just moved to the US from Mexico, said that she had only put on 10 pounds in weight during her pregnancy and that even her aunt, who lives with her, didn't know she was expecting a child.

She gave birth alone after two hours of "excruciating" labour. She was too afraid to cut the umbilical cord and had no clothes for the baby.

The woman said that the child's lips turned purple as she walked with him to the Holy Child Jesus Church in Queens so she ran into a store and bought a towel to wrap him in.

"He was crying. I just prayed he was warm enough. I knew the priest would find him, and somebody would help him," he said.

Police have agreed not to prosecute her because the case falls under the "safe haven" law, which says that a newborn baby can be dropped off anonymously at a church, hospital, police or fire station without fearing prosecution.

The baby was found around by a custodian who left the empty chapel in order to get lunch. He was unaware of the baby's presence until it started crying.

The mother has not yet decided whether to keep the child, saying that she needs secure employment before she can take on the responsibility. However, a young couple from the church have expressed hope that they will be allowed to take in the newborn, a priest at the Holy Child Jesus Church said.

"A young couple in our parish would love to adopt this child and keep this gift in our community. It would make a great Christmas miracle," Father Christopher Heanue said.

"The beautiful thing is that this woman found in this church – which is supposed to be a home for those in need – this home for her child."