Romney not worried about Santorum, labels Russia No. 1 'foe'

(CNN) - Republican presidential candidate Mitt Romney said Monday he was unfazed by recent ramped-up rhetoric coming from his opponent Rick Santorum.

"I'm not going to worry too much about what Rick is saying these days," Romney said on CNN's "The Situation Room with Wolf Blitzer." "I know when you're falling further and further behind, you get a little more animated."

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Santorum made headlines Sunday when he claimed Romney would be the "worst" Republican candidate to match up against President Barack Obama in the general election, based on the issue of health care reform.

The former Massachusetts governor, he argued, would be poorly armed in a fight against the president after signing off on a health care law in the Bay State that critics now label a "blueprint" for the controversial federal health care legislation passed in 2010.

Romney argues, however, that he would attempt to repeal the Affordable Care Act as president, saying states should have the right to regulate health care laws, not Washington.

"It's a power grab by the federal government. It violates the 10th Amendment. It violates the economic principles and economy freedom in this country," Romney said on CNN. "It needs to be repealed."

The candidate also blasted Obama over a private conversation caught by microphone with Russian President Dmitry Medvedev, in which the president said he could be more flexible on the missile defense system in Europe after the election.

Romney joined other top Republicans in slamming the president over the remark on Monday and for making backroom deals with a country that Romney called America's "Number One geopolitical foe."

“Who is it that always stands up with the world's worst actors? It's always Russia, typically with China alongside. In terms of a geopolitical foe, a nation that’s on the Security Council, and as of course a massive nuclear power, Russia is the geopolitical foe. The idea that our president is planning on doing something with them that he's not willing to tell the American people before the election is something I find very, very alarming,” Romney said.

The White House hopeful also opened up about how he spent some recent time-off from the campaign trail, saying he went to watch "The Hunger Games" with his grandchildren over the weekend.

"I read serious books, but every now and then I read just for fun," Romney said, talking about how he read the book before seeing the movie. "That was weekend fun, so it was nice to see a flick for the first time in a long time."

Also see:

Santorum: Romney 'worst Republican' to run against Obama

Ryan's open to V.P spot

Graham's 'comfortable' with Romney

Plouffe calls out GOP candidates over Obama reaction

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