Ted CruzRafael (Ted) Edward CruzDebbie Wasserman Schultz marks 10 years as breast cancer survivor Foreign agent registration is no magical shield against Russian propaganda Let Trump be Trump and he'll sail through 2020 MORE ratcheted up his rhetoric against Donald TrumpDonald John TrumpHouse Democrat slams Donald Trump Jr. for ‘serious case of amnesia’ after testimony Skier Lindsey Vonn: I don’t want to represent Trump at Olympics Poll: 4 in 10 Republicans think senior Trump advisers had improper dealings with Russia MORE on Monday, suggesting his Republican presidential rival's "entire campaign is built on a lie" amid similarly harsh rhetoric from the businessman.

"Every time Donald gets scared, he begins lashing out, he begins attacking, he begins insulting, he begins yelling, often he begins cursing," the Texas senator said during an interview with Wolf Blitzer broadcast Monday evening on CNN. "I will say this: Donald's campaign, his entire campaign is built on a lie."

Cruz went on to acknowledge that many of those supporting Trump see him as a political outsider but argued, "If you're fed up with Washington, with the corruption of Washington, then it doesn't make any sense to support Donald Trump, who has been enmeshed in the corruption of Washington.

"The lie behind Donald's campaign is that he will stand up to Washington. He is the system," Cruz continued. "Donald Trump and Hillary ClintonHillary Diane Rodham ClintonGrassley blasts Democrats over unwillingness to probe Clinton GOP lawmakers cite new allegations of political bias in FBI Top intel Dem: Trump Jr. refused to answer questions about Trump Tower discussions with father MORE are flip sides of the same coin: Donald Trump has made billions buying influence in Washington; Hillary Clinton has made millions selling influence in Washington."

The remarks came after CNN played comments from Trump over the weekend in which he blasted Cruz for formerly being a "citizen of Canada,” repeatedly referring to the Texas senator as "lying Ted."

"One of the biggest liars I've ever seen in my life, I really mean it," Trump said. 

Cruz pushed back during his CNN interview, knocking Trump on eminent domain and also accusing him and Democratic front-runner Hillary Clinton of "empty campaign rhetoric" in their respective remarks on Israel earlier in the day, including Trump's promise of moving the U.S. Embassy from Tel Aviv to Jerusalem. 

Cruz, who is running second to Trump in the delegate count, is aiming to deny the businessman the needed 1,237 delegates to lock up the nomination before the party's convention in July.

He insisted to CNN he had "zero interest whatsoever" in being Trump's running mate, saying it would be a "disaster" if Trump were the nominee, predicting a defeat to Clinton.

He also went after President Obama on the day he met with Cuban President Raúl Castro, charging, "As Barack ObamaBarack Hussein ObamaPatagonia files suit against Trump cuts to Utah monuments Former Dem Tenn. gov to launch Senate bid: report Eighth Franken accuser comes forward as Dems call for resignation MORE is there sipping mojitos with brutal communist dictators, he can't be bothered to meet the dissidents."

Also in his interview, Cruz defended Frank Gaffney, his controversial newly named foreign policy adviser who questioned President Obama's birthplace, whom Cruz described as "someone I respect" and a "serious thinker."