Republican presidential front-runner Donald Trump stepped up his personal attacks on GOP rival Ted Cruz Sunday, just two weeks before the Iowa caucuses and as the Texas senator is gaining some ground on the real estate tycoon. Appearing on ABC's This Week, Trump called Cruz a "nasty guy" and a "total hypocrite" as he spoke about Cruz's recently discovered loans to bankroll his 2012 senate bid and his eligibility for the White House.

"I don't think Ted Cruz has a great chance, to be honest with you," Trump told host George Stephanopoulos in the interview, which aired on Sunday, ABC News reported. "Look, the truth is, he's a nasty guy. He was so nice to me. I mean, I knew it. I was watching. I kept saying, 'Come on Ted. Let's go, okay.' But he's a nasty guy. Nobody likes him. Nobody in Congress likes him. Nobody likes him anywhere once they get to know him."

Trump also hit Cruz on his failure to disclose to the Federal Election Commission (FED) two loans totalling approximately $1 million that he used to fund his 2012 bid for the senate.

"He's a total hypocrite. How about his fundraising and how about when he does his personal financial disclosure form, and he doesn't put on that he's borrowing money from Goldman Sachs? And then today it comes out that he's also borrowing money from CitiBank and he doesn't list it." said Trump. "You know why? He wants to look like Robin Hood that he's the one protecting the people from the banks while he's actually borrowing money and personally guaranteeing it and not disclosing it, which is illegal," he added, according to Politico.

On the issue of Cruz's Canadian birthplace and his eligibility for the White House, Stephanopoulos told Trump that some legal scholars indicate that the real estate mogul could launch a lawsuit against Cruz.

"Oh, that's an interesting case. Wow, that sounds like a very good case. I'd do the public a big favor," Trump responded, without saying whether he'd actually file such a suit, the Daily Caller reported. "It's a good idea -- maybe I'll talk to them about it. I'd like to talk to Ted about it, see how he'd feel about it. 'Cause you know, when I file suits, I file real suits."

For most of the campaign season thus far, the two had an unusually friendly relationship for competitors seeking the Republican nomination. That began to change, however, when a secret recording surfaced last month of Cruz questioning Trump's judgment at a Republican fundraiser, The New York Times reported.