The panel on "The Five" reacted to Sen. Elizabeth Warren (D-Mass.) floating a tax of at least two percent on Americans earning more than $50 million per year.

Warren tweeted the proposal Thursday as part of her 2020 presidential bid.

Warren has long railed against income inequality and the uber-rich, but would mark a move to the left by the party as a whole if it were adopted.

The plan also would include mechanisms to combat tax evasion, such as more funding for the IRS, a measure to require all those paying the wealth tax be subject to an audit and a one-time penalty for those with over $50 million who have tried to renounce citizenship, according to the Washington Post.

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Warren’s campaign did not immediately respond to a request for comment from Fox News for its original story.

Marie Harf said that, although Warren is not a top choice for her going into 2020, the lawmaker is "raising an issue" that is important to national discourse.

"We have still not figured out how to solve [the problem] with economic inequality," she said.

Harf said the Trump tax cuts were "geared toward higher income brackets" and that the middle class need better relief.

Watch more above.

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