Story highlights

After the Texas Republican's comments at a private fundraiser have leaked, Trump is signaling he's ready to throw down.

Though Cruz also said he "like(s) and respect(s)" Trump and Carson, he questioned their fitness to lead the country

Washington CNN  — 

The most enduring love-fest in the 2016 presidential race may soon be coming to an end, and Donald Trump is licking his chops.

The GOP front-runner has pledged repeatedly during the primary to only go after his opponents after they attack – and the outspoken mogul has thus far been unable to justify aiming his sharp tongue at surging rival Sen. Ted Cruz, who has only spoken well of his opponent on the trail.

But now that the Texas Republican’s comments at a private fundraiser have leaked, Trump is signaling he’s ready to throw down.

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”.@tedcruz should not make statements behind closed doors to his bosses, he should bring them out into the open – more fun that way!” Trump tweeted Friday morning.

“Looks like @tedcruz is getting ready to attack. I am leading by so much he must. I hope so, he will fall like all others. Will be easy!” he added.

Trump was responding to audio obtained by The New York Times of Cruz speaking at a private fundraiser this week, where Cruz made transparent remarks about his strategy to pick off Trump and Ben Carson voters by not going on attack.

“My approach, much to the frustration of media, is to bear hug both of them and smother them with love,” Cruz said. “I believe that gravity will bring both of those candidates down. I think the lion share of their supporters will come to us.”

Though Cruz also said he “like(s) and respect(s)” Trump and Carson, he questioned their fitness to lead the country.

“You look at Paris, you look at San Bernardino, it’s given a seriousness to this race,” Cruz said. “People are looking for who is prepared to be a commander in chief. Who understands the threats we face. ‘Who am I comfortable having their finger on the button?’ Now that’s a question of strength, but it’s also a question of judgment. And I think that is a question that is a challenging question for both of them.”

It’s the most critical language of Trump to come from Cruz in the race. The senator, who appeals to evangelical voters and Americans frustrated with government that have flocked to Trump and Carson in droves this cycle, has made a conscious effort to avoid going negative against the primary leaders – even appearing with Trump at a Capitol Hill rally on the Iran nuclear deal.

Cruz’s hesitance to criticize Trump directly – even after Trump put forward a policy to ban all foreign Muslims from entering the country – stands in contrast with many of his fellow candidates, who have increasingly sharpened their criticism of the front-runner and expressed frustration with his success in the polls.

Trump is scheduled to hold a campaign rally Friday night in Iowa – the key early caucus state where Cruz has recently surged in recent polls.

Cruz on Friday was clearly aware of the narrative the story was taking. He downplayed the likelihood of a public rift, tweeting, “The Establishment’s only hope: Trump & me in a cage match. Sorry to disappoint – @realDonaldTrump is terrific. #DealWithIt”

Several hours later, Trump appeared to join Cruz in that sentiment and retweeted the Texas senator’s tweet – extending the pair’s détente.

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