Former HP chief executive and White House hopeful Carly Fiorina slammed Donald Trump over the GOP front-runner's incendiary comments about undocumented immigrants and his suggestion to end birthright citizenship.

"I've been very clear I don't support deportation. I don't support amending the Constitution or challenging the 14th Amendment," Fiorina told NBC News. "I think these are ideas that stoke anger but don't solve problems. I think Donald Trump is stoking anger without solving problems. And I think others, now, are sadly pandering to him."

Fiorina and Trump have been in an increasingly vocal public feud ever since the businesswoman stood out in a Fox News debate of second-tier Republicans last month, an event at which she characterized the real estate tycoon as a flip-flopping Democrat-in-disguise, the New York Post recalled.

"Since he has changed his mind on amnesty, on health care and on abortion, I would just ask: What are the principles by which he will govern?" Fiorina quipped. "I didn't get a phone call from Bill Clinton ... Maybe it's because I hadn't given money to the foundation or donated to his wife's Senate campaign."

Trump, for his part, responded by ridiculing Fiorina on social media. "I just realized that if you listen to Carly Fiorina for more than 10 minutes straight, you develop a massive headache," the "Apprentice" star noted on Twitter, according to the Washington Examiner.

The two will soon be able to debate face-to-face, after CNN changed the rules for its GOP debate set on Sept. 16, a victory the Fiorina camp scored in a high-volume public relations campaign. And though he was not pleased that 11 people would be on the podium, Trump suggested that he welcomed Fiorina as a worthy challenger.

"I think it's great. ... I was in favor of her being - I think she should be in the debate," the front-runner said in a Thursday press conference in New York. "I was very happy that she got into the debate because, frankly, she deserved to be in the debate."