Mitt Romney fries Donald Trump in an epic speech

Mitt Romney railed on GOP presidential frontrunner Donald Trump in a major address Thursday, calling him a "phony," "fraud," "con man," and a "fake."

%shareLinks-quote="Let me put it plainly, if we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished." type="quote" author="Mitt Romney" authordesc="Former Mass. Governor" isquoteoftheday="false"%

Romney's speech came as the Republican establishment grows increasingly worried about the growing potential of a Trump nomination. It was delivered two days after Trump scored a dominating victory during the "Super Tuesday" primaries and caucuses.

RELATED: Reaction to the speech on social media

Romney's speech -- remarkable in that the party's most recent nominee was launching an unprecedented assault against its current frontrunner -- went after Trump's business history, policy proposals, and fitness for office.

Listing many of Trump's previous businesses, like Trump Steaks, Trump Airlines, and the controversial Trump University, Romney said Trump isn't a "business genius."

READ MORE: 2008 Republican nominee John McCain joins Romney in blasting Trump

After then speaking about a remark Trump said on "60 Minutes," in which he said the US should let Syrian President Bashar al-Assad "take out ISIS," Romney said his foreign policy is "reckless."

RELATED: Trump on the campaign trail

"Donald Trump tells us that he is very, very smart," Romney said.

%shareLinks-quote="I'm afraid that when it comes to foreign policy [Donald Trump] is very, very not smart." type="quote" author="Mitt Romney" authordesc="Former Mass. Governor" isquoteoftheday="false"%

"Here's what I know: Donald Trump is a phony, a fraud," Romney said. "His promises are as worthless as a degree from Trump University. He's playing the American public for suckers. He gets a free ride to the White House and all we get is a lousy hat," he continued.

Romney, who recently has been publicly critical of Trump's campaign, gave his Thursday morning speech at the Hinckley Institute of Politics at the University of Utah in Salt Lake City.

"His domestic policies would lead to recession," Romney said later. "His foreign policies would make America and the world less safe. He has neither the temperament nor the judgment to be president. And his personal qualities would mean that America would cease to be a shining city on a hill."

Data is curated by insidegov.com

He went on to say that, should Trump win his party's nomination, the election will be handed to a "dishonest" Hillary Clinton, the former secretary of state who is the Democratic frontrunner.

"Trump relies any poll that reflects what he thinks of himself. But polls are also saying that he will lose to Hillary Clinton," he said.

He added that Trump's challengers -- Ohio Gov. John Kasich and Sens. Ted Cruz of Texas and Marco Rubio of Florida -- are the only candidates with "serious policy proposals."

The 2012 GOP presidential nominee also channeled former US President Ronald Reagan in his speech, referencing a 1964 address Reagan made about the future of the country.

"I'm no Ronald Reagan and this is a different moment but I believe with my heart and soul that we face another time for choosing, one that will have profound consequences for the Republican Party and more importantly, for the country," he said.

Romney also called out Trump for calling former US President George W. Bush a "liar" and also said Trump "admires" Russian President Vladimir Putin.

"That is a twisted example of evil trumping good," he said.

He went on to explain how he understands the anger that the national electorate feels -- anger that has led to Trump's rise within the party. But, Romney -- in another slight at Trump -- said, in the past, anger from voters was "transformed into energy directed for good" by past presidents.

Trump, he insinuated, wouldn't be the best example for future generations.

"The president and yes, the nominees of the country's great parties help define America to billions of people," Romney said. "All of them bear responsibility of being an example for our children and grandchildren."

Romney in recent days has been locked in a back-and-forth with Trump, whom he's denounced for dodging questions about the Ku Klux Klan and for not releasing his tax returns.

"A disqualifying & disgusting response by @realDonaldTrump to the KKK. His coddling of repugnant bigotry is not in the character of America," Romney tweeted on Monday after Trump said in an interview that he didn't know enough about former KKK Grand Wizard David Duke or white supremacists to denounce them.

Trump later attributed his answer to a faulty earpiece.

On taxes, Romney has repeatedly suggested Trump could be hiding a "bombshell" in his returns. He insisted Thursday that Trump must release his tax returns and added he thinks Trump doesn't do "much if anything" for disabled Americans and veterans.

"Well, I think there's something there," Romney told Fox News host Neil Cavuto last week. "Either he's not anywhere near as wealthy as he says he is, or he hasn't been paying the kind of taxes we would expect him to pay. Or perhaps he hasn't been giving money to the vets or the disabled, like he's been telling us he's been doing."

Trump has unleashed multiple tirades against Romney on social media and in public.

"Watch how he responds to my speech today," Romney said Thursday. "Will he talk about our policy differences or will he attack me with every imaginable low road insult? This may tell you what you need to know about his temperament, his stability, and his suitability to be president."

Last week, Trump tweeted that Romney was one of the "dumbest and worst" Republican candidates to ever run for president.

"I criticized Mitt Romney for losing that election. He should have won that election," Trump said during last week's GOP debate in Houston.

After bits of Romney's speech were leaked early Thursday morning, Trump took to Twitter to unleash a scathing series of tweets at the former governor.

See the series of tweets in the gallery below:

Trump is two days removed from a big "Super Tuesday" win, where he captured at least seven of the states that held primaries or caucused (Colorado does not release the results of its Republican caucus).

The real-estate mogul holds a nearly 100 delegate lead over Cruz, who is in second place, and he has a more than 200-delegate lead over Rubio. Trump is also leading the polls in Michigan, Ohio, Florida, North Carolina, and Illinois, the five largest states that hold elections within the next two weeks.

RELATED: Super Tuesday across America

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