US presidential candidate Rick Santorum told a group on his campaign trail in Iowa that gay marriage would damage “family and faith” by forcing schools to teach children about gay and straight relationships equally, ABC reports.

A recent graduate of a Christian college in Sioux Center pressed Santorum on why gay marriage would be “a hit to faith and family in America”.

Santorum said that legalising same-sex marriage meant the “sexual activity” of gays would be “seen as equal” to that of straight people. As a result, he said, it would be taught equally in schools.

Santorum said: “So what is going to be taught to our people in health class in our schools? What is going to be taught to our children about who in our stories, even to little children — what are married couples? What families look like in America?

“So, you are going to have in our curriculum spread throughout our curriculum a world view that is fundamentally different than what is taught in schools today? Is that not a consequence of gay marriage?”

The student who was questioning him said he did not agree with Santorum’s view.

Santorum replied: “I think you’re wrong — okay, in fact you have to know you’re wrong, because if we say legally if this type of relationship is identical to other type relationships than of course more of it will be taught because this is what the law says.”

Rick Santorum announced his candidacy for next year’s Republican presidential nomination this summer.