Pennsylvania Governor Tom Corbett has apologized for comparing gay marriage to incest.

The Republican governor angered marriage equality advocates with his remarks made Friday morning during an appearance on Harrisburg's WHP-TV.

Corbett was asked about a statement his lawyers made in a recent court filing to stop a county clerk from issuing marriage licenses to gay and lesbian couples. The lawyers argued that licenses issued to gay couples are invalid because such couples – like “12-year-olds” – can't marry.

“It was an inappropriate analogy, you know. I think a much better analogy would have been brother and sister, don't you?” Corbett, an opponent of marriage equality, answered with a smile.

“I don't know,” the anchor responded.

(Watch video of the interview at our video library.)

Corbett, a former state attorney general, added that he does not believe a pending challenge to the state's marriage ban belongs in federal court.

Ted Martin of Equality Pennsylvania, the state's largest LGBT rights advocate, called Corbett's remarks “shocking and hurtful.”

“Gov. Corbett's comments aren't simply offensive; they're out of touch,” Martin said.

Within hours, Corbett apologized in a written statement.

“My words were not intended to offend anyone,” he wrote. “If they did, I apologize.”

“I explained that current Pennsylvania statute delineates categories of individuals unable to obtain a marriage license. As an example, I cited siblings as one such category, which is clearly defined in state law. My intent was to provide an example of these categories.”

(Related: Gay marriage bill introduced in Pennsylvania House.)