The former House Speaker, who has been a passionate defender of Trump over the past few weeks, says that his statement that a federal judge's Mexican heritage makes the judge biased agaisnt him is one of Trump's "worst mistakes."
"He has every right to criticize the judge, and he has every right to say certain decisions aren't right, and his attorneys can file to move the venue... but... this judge was born in Indiana. He's an American, period."
"Trump has got to move to a new level," Gingrich said. "This is no longer the primaries, he is no longer an interesting contender, he is a potential leader of the United States. And he's got to move his game up."
Full interview on Fox News Sunday: