Tuesday on MSNBC’s “Morning Joe,” Republican presidential front-runner Donald Trump took aim at his opponent Sen. Ted Cruz (R-TX) in what is seeming an escalating rivalry on with a week to go before the Iowa caucuses.

Trump was asked to react an attack ad from the Cruz campaign that included Trump’s pro-choice remarks from a “Meet the Press” interview from 1999 and a comments from a rally he made taking a shot at Ben Carson for the contents of his book, “How stupid are the people of Iowa?”

“[T]ed Cruz lies,” Trump said. “He’s a liar. That’s why nobody likes him, that’s why his Senate people won’t endorse him. That’s why he stands in the middle of the Senate floor and can’t make a deal with anybody. He looks like a jerk, he’s standing all by himself. And you know, there’s something to say about having a little bit of ability to get other people to do things. You can’t be a lone wolf and stand there. That’s sort of what we have right now as a president. We have a president that can’t get anything done so he just keeps be signing executive orders all over the place.”

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