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Is the relationship between Republican presidential contenders Donald Trump and Ted Cruz souring?

On Friday, Trump launched his first attacks against Cruz, questioning not only the Texas senator's ties to big oil companies, but also his appeal to evangelical voters.

"I do like Ted Cruz, but not a lot of evangelicals come out of Cuba," Trump told the crowd at a town hall event in Des Moines, Iowa. "Not a lot come out."

On "Fox and Friends Weekend" this morning, Trump explained that he was just having a little fun with Cruz, who he said has been very supportive on the campaign trail.

He said that he and Cruz like each other and have many similar positions, although they do have their differences. In particular, Trump said he would give himself the advantage when it comes to "temperament."

"We've had a very good relationship," Trump said. "But I'm sure it will end, because he's got to come after me at some point. I'm leading by a lot, as you know, so at some point he's going to come after me."

What's going to happen when he comes after you? Tucker Carlson asked.

"Well, then I go after him," Trump said. "So far, that's worked. Look at the long list. So far, it's been working."

Watch more above.

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