Pope Francis has endorsed civil unions between same-sex couples for the first time since becoming pontiff in 2013.

In the book Politics and Society, which consists of 12 printed conversations between the pope and French sociologist Dominique Wolton, he discussed his feelings on marriage equality and explained that he prefers using a different term to describe the union of gay people.

"'Marriage' is a historical word. Always in humanity, and not only within the Church, it's between a man and a woman...we cannot change that. This is the nature of things," he said. "Let's call them 'civil unions.' Let's not play with the truth."

"Let's say things as they are: Marriage is between a man and a woman," he added. "This is the precise term. Let's call unions between [same-sex couples] 'civil unions.'"

Pope Francis has spoken out against marriage equality before, but this is the first time he gave an official endorsement to same-sex civil unions. Public Now pointed out that he did say he'd support them while he was an archbishop in Argentina, but that all his previous statements on civil unions since becoming the pope have been vague and ambiguous until now.

The pontiff goes on to speak about gender identity, and accuses schools of teaching children that they have the ability to decide what gender they want to be.

"In books, also, children are learning that they can choose their own sex," he said. "Why is sex, being a woman or a man, a choice and not a fact of nature? This favors this mistake."

Pope Francis has certainly been more progressive when it comes to LGBT issues than any pope before him, but the pontiff consistently sends mixed signals when it comes to his feelings on gay rights, indicating there is still a long way to go to erase stigma and bigotry within the Catholic Church.