Sen. Bernie Sanders (I-Vt.) described President Donald Trump's claim that Democrats are obstructing progress on tax overhaul efforts in Congress as "total nonsense" on Sunday.

"This is a terrible, terrible piece of legislation and it must be defeated." —Sen. Bernie Sanders"Democrats," Sanders told Jake Tapper on CNN's Face The Nation, "have been shut out of this process just as they were shut out of the healthcare legislation process."

Going further, Sanders said that Trump "should understand" exactly what's going on and why Democrats, as well as a large majority of the U.S. public, do not like or trust what the Republicans in Congress are attempting to do with what they call "tax reform" but which progressive critics have identified—and numerous analyses have shown—as nothing more than a "tax scam" that gives to the rich at the expense of the lower- and middle-classes.

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"What this is about," said Sanders, "is fulfilling Republican promises made to wealthy campaign contributors. There is a reason why the billionaire class provides hundreds of millions of dollars in campaign contributions to Republicans. And now is payback time. What this legislation is about, Jake, is giving 50% of the tax benefits to the top 1% — and at the end of ten years in the House bill, forcing almost 50% of the middle class to actually pay more in taxes."

"What this tax reform bill is about—absolutly and insanely," he continued, "is repealing the estate tax; a $265 billion tax break, not for the top 1% but for the top 0.2%—a handful of the wealthiest families in this country, like the Walton family and the Koch brothers." All of this, Sanders concluded, as the Republicans willingly explode the annual deficit by $1.5 trillion in order to later argue that Social Security, Medicare, and Medicaid must be cut. "This is what [Speaker of the House] Paul Ryan is saying. They're gonna come back with massive cuts [to those programs], because they say, 'Oh my goodness, the deficit and the national debt are too high.' This is a terrible, terrible piece of legislation and it must be defeated."