Fox News/screenshot
Fiorina, who like Trump is competing for the Republican presidential nomination, predicted Tuesday that Trump would lose to former Secretary of State Hillary Clinton, the Democratic front-runner.
"Donald Trump is Hillary Clinton's Christmas gift wrapped up under a tree," Fiorina said during an interview on Fox News' "America's Newsroom."
"Because if he were to be our nominee - and I do not think he will be - Hillary Clinton will wipe the floor with him and we will lose the Senate, we may well lose the House," Fiorina continued. "I am the lump of coal in her stocking. I can beat Hillary Clinton and I can turn this government into something competent that serves its people and protects its nation."
Fiorina had a series of criticism's of Trump's proposal to stop all Muslim tourists and immigrants from entering the US until the religion's terrorism "problem" is figured out.
"I think his overreaction is as dangerous as Barack Obama's under-reaction," Fiorina said, arguing that Trump's plan was illegal. "Donald Trump is saying the government is incompetent and therefore let's trample on the Constitution by holding a religious test, which is most definitely a violation of our Constitution."
Fiorina, who has tangled with Trump on the campaign trail, went on to criticize the press for being overly fixated on Trump's outrageous statements.
"The media plays into this every time," she said. "Donald Trump says something, and that's all we talk about."
Watch Fiorina's interview below: