Trump rants about 'unfair' judge's 'Mexican heritage' in bizarre CNN interview
Donald Trump speaks to CNN on June 3, 2016.

GOP candidate Donald Trump doubled down on his attack of a judge overseeing a lawsuit against his "Trump University" venture, which has been described by critics as a scam, cannot be unbiased in the case because he is of Latino descent, CNN reports.

On Friday in an interview with CNN's Jake Tapper, in which Tapper asked multiple times whether Trump thought it was right to invoke the race of the judge involved, Trump didn't back down.

"I think that's why he's doing it," Trump said, when Tapper questioned him. He insisted he should have won the case and would have, if the judge involved weren't Latino.

"I have had horrible rulings, I've been treated very unfairly by this judge. Now, this judge is of Mexican heritage," Trump said. "I'm building a wall, okay. I'm building a wall. I am going to do very well with the Hispanics, the Mexicans."

Tapper then cut him off and pressed, "So, no Mexican judge can ever be involved in a case that involves you?"

Trump insisted the judge, who is an American citizen hailing from Indiana, is biased because Trump has vowed to build a wall at the U.S.-Mexico border.

"Jake, I'm building a wall, okay? I'm building a wall," Trump said. "I'm trying to keep business out of Mexico."

When Tapper pointed out the judge is American, Trump responded, "But he's of Mexican heritage."

Trump continued to insist that the only reason the case against Trump U hasn't been dismissed is because of the judge's Mexican heritage.

Watch the interview, as posted by CNN digital producer Deena Zeina Zaru, here: