Story highlights Marco Rubio hit Ted Cruz on foreign policy Sunday, calling him an isolationist

Rubio cited Cruz's votes against budget bills and for a program that limited government data collection

(CNN) Marco Rubio says he isn't buying Ted Cruz's tough talk on national security.

The Florida senator hammered Cruz for opposing the U.S. government's bulk phone data collection and voting against spending bills and defense authorization acts -- suggesting Cruz's voting record is that of an isolationist -- in an interview on NBC's "Meet the Press" Sunday.

"He talks tough on some of these issues. For example, he was going to carpet bomb ISIS. But the only budget he's ever voted for in his time in the Senate is a budget that cut defense spending by more than Barack Obama proposes we cut it," Rubio said of Cruz, his rival for the Republican presidential nomination.

"He voted against the Defense Authorization Act every year that it came up. And I assume that if he voted against it, he would veto it as president," Rubio said.

"That's the bill that funds our troops. Even the Iron Dome for Israel. So I guess my point is each time he's had to choose between strong national defense and some of the isolationist tendencies in American politics, he seems to side with the isolationist," Rubio said. "And this is an important issue to have a debate over. It's not personal."

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