Story highlights Bernie Sanders defended pricey proposals to expand Medicare and spend on infrastructure and college

Sanders said the United States should raise taxes on the wealthy and corporations

Washington (CNN) Vermont Sen. Bernie Sanders says the federal budget deficit is a "serious problem" -- but he's not backing away from potentially pricey policy proposals.

In an interview with NBC's Chuck Todd set to air Sunday on "Meet the Press," the Democratic presidential contender said he'd pay for his plans -- including $1 trillion for infrastructure and a "Medicare for all" health insurance system -- through higher taxes on wealthy Americans and corporations that keep profits outside the country.

"You take a hard look at our tax system," Sanders said when pressed about how he'd address the deficit.

"And you say, 'You know what? Corporate America, you ain't going to stash your money in the Cayman Islands and not pay any taxes at all,'" he said. "If you are very, very wealthy, as Warren Buffett reminds us, you know what? You're not going to continue to pay an effective tax rate lower than middle class people."

Sanders pointed to wars in Iraq and Afghanistan "that our Republican friends got us into and forgot to pay for," as well as George W. Bush-era tax cuts for the wealthy and for corporations, as the culprits for a national debt that has topped $18 trillion and increases each year.

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