Recently, Republican presidential candidate Donald Trump has been raising the question of his rival Ted Cruz’s eligibility to be president, implying that, because he was born in Canada, he is not a “natural-born citizen.” He is, of course, but that hardly seems to matter.

“You can’t have a person who’s running for office, even though Ted is very glib and he goes out and says ‘Well, I’m a natural-born citizen,’ but the point is you’re not,” Trump said during a campaign stop in Iowa this weekend. Cruz was born in Calgary, Canada to an American mother and a Cuban father who said, at a campaign event during his son’s 2013 senate campaign, that Barack Obama should “go back to Kenya.”

Trump said he thinks Cruz should get the Supreme Court to rule on the matter. “Let me tell you: From Ted’s standpoint and from the party’s standpoint, he has to solve this problem, because the Democrats will sue him if he’s the nominee,” he said Sunday on NBC’s “Meet the Press.” “If Ted is the nominee, he will be sued by the Democrats.”

On “Fox News Sunday,” Trump said that he was not “trolling” Cruz. “He should take it very seriously. You know what? I think I’m going to win. I don’t want to beat him in this way,” he said. “I’m just saying, in my opinion, and you already seen it—the Democrats are going to bring a lawsuit. If [the nominee is] Ted, the Democrats are going to bring a lawsuit. He’s got to have this thing worked out.”

Cruz dismissed Trump’s line of thinking out of hand. “The substance of the issue is clear and straightforward. As a legal matter, the Constitution and federal law are clear that the child of a U.S. citizen born abroad is a natural-born citizen,” he said Sunday on CNN’s “State of the Union.” “Three weeks ago, almost every Republican candidate was attacking Donald Trump. Today, almost every Republican candidate is attacking me. That kind of suggests maybe something has changed in the race.”

Cruz renounced Canada after his dual citizenship was revealed by the Dallas Morning News in 2013. Apparently, he didn’t even know he was a Canadian citizen.

Photo via AP Images. Contact the author of this post: brendan.oconnor@gawker.com.