WATCH: Scott Walker Wants to Amend the Constitution to Ban Marriage Equality

Taking a page from the legislative playbook of presidential hopeful Ted Cruz, Wisconsin Gov. Scott Walker supports amending the U.S. Constitution to ban same-sex marriage if the Supreme Court issues a pro-equality ruling later this month.

Walker, a likely Republican presidential candidate who had not formally declared his candidacy, spent much of the past two years keeping quiet about his thoughts on marriage equality.

But in an interview with ABC News correspondent Jonathan Karl broadcast Sunday, Walker cut to the chase.

"I personally believe that marriage is between one man and one woman," said the Republican governor.

When Karl asked how Walker would respond to a ruling from the U.S. Supreme Court that found a constitutional right for same-sex couples to marry, Walker was similarly to-the-point.

"If the court decides that, the only next approach is for those who are supporters of marriage being defined as between one man and one woman is ultimately to consider pursuing a constitutional amendment."

Karl pressed the governor, asking if he was supporting an amendment to the Constitution that would "allow states to ban same-sex marriage."

"I believe that the decision on defining marriage should be left up to the states, yeah," Walker concluded.

Despite the fact that Walker has not declared his candidacy, LGBT blog The New Civil Rights Movement notes that the Wisconsin governor is "leading several of the GOP 2016 presidential polls currently."

When Karl attempted to get Walker to weigh in on former Olympian Caitlyn Jenner's recent coming-out as a trans woman, Walker curtly refused to comment, saying only that "it's a personal decision." That's a marked difference in tone from presidential hopeful Lindsey Graham, who said he would welcome the self-described Republican to the party, and asked for Jenner's vote. Graham also indicated that he was prepared to accept and respect the court's decision on marriage equality.

Watch Walker's interview below, with the marriage equality comments beginning at the 5:30 mark.
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