Real estate tycoon Donald TrumpDonald TrumpCapitol fencing starts coming down after 'Justice for J6' rally Netanyahu suggests Biden fell asleep in meeting with Israeli PM Aides try to keep Biden away from unscripted events or long interviews, book claims MORE cast doubt Monday on whether Sen. Ted CruzRafael (Ted) Edward CruzO'Rourke prepping run for governor in Texas: report Support for Abbott plunging in Texas: poll White House debates vaccines for air travel MORE (R-Texas) can run for president, because Cruz was born in Canada.
"It’s a hurdle; somebody could certainly look at it very seriously," Trump said during a phone interview Monday on My Fox New York.
"He was born in Canada. If you know and when we all studied our history lessons, you are supposed to be born in this country, so I just don't know how the courts will rule on this."
Trump, who says he is exploring a bid for president in 2016, was part of the "birther" movement that questioned President Obama's birth place, as well as the veracity of his birth certificate. He recently took credit for getting Obama to release his birth certificate while speaking at the Conservative Political Action Conference in February.
After flirting with a 2012 presidential bid, Trump has announced an exploratory committee for 2016 and says he will not renew his contract for his TV show, "The Apprentice" on NBC.
Cruz confirmed his bid for president on Monday morning during a speech at Liberty University.
“It’s going to take a new generation of courageous conservatives to help make America great again, and I’m ready to stand with you to lead the fight," he said in a video touting the speech.
Trump claimed he had come up with Cruz's line about making America great again and questioned whether he should have secured the rights to it ahead of the 2016 campaign.
"The line of 'Make America great again,' the phrase, that was mine, I came up with it about a year ago, and I kept using it, and everybody's now using it, they are all loving it," Trump said.
"I don’t know I guess I should copyright it, maybe I have copyrighted it."