The Catholic Church said that it is "impossible to allow" transgender people to be godparents, according to a Spanish bishop who was informed by the Vatican after he asked for specification on the issue.

Bishop Rafael Zornoza Boy had consulted Vatican officials to specify the church's stance on this question to help clarify confusion after Alex Salinas, a 21-year-old transgender male in the Cadiz and Ceuta diocese, asked to be his nephew's godfather in June.

In a statement delivered on Tuesday, the bishop recounted how the Vatican's doctrinal arm had informed him that transgender people "publicly show an attitude contrary to the moral requirement to resolve one's sexual identity problem according to the truth of one's own sexuality."

"Therefore it is evident that this person does not possess the requirement of leading a life according to the faith and in the position of godfather and is therefore unable to be admitted to the position of godfather or godmother," he was told.

Zornoza Boy also noted that Pope Francis has repeatedly stated "that this behavior is contrary to human nature."

That said, the Vatican emphasized that its position on this matter is not discriminatory, insisting instead that transgender individuals simply lack the requirements that "are necessary to assume the ecclesial responsibility of being a godfather."

Church officials pointed out that godparents are not necessary for a Catholic baptism if the parents cannot find suitable candidates.

The Vatican does not have a formal stance on the inclusion or exclusion of transgender people from the church. At a 2012 Christmas sermon, Pope Benedict made it clear that gender was binary between male and female, and established at birth.

"According to the biblical creation account, being created by God as male and female pertains to the essence of the human creature," Benedict said. "This duality is an essential aspect of what being human is all about."

In 2014, Tia Pesando became the first transgender Catholic nun when she was accepted to the Carmelite Sisters' novitiate in Canada.