WATCH: Biden admin wants to tax increased value of assets before those assets are sold

Yellen said that unlike Speaker Nancy Pelosi she would not call it a "wealth tax" but a tax on "unrealized capital gains" for the "exceptionally wealthy."

This means Yellen wants to tax the increase in value on your home before you've sold it, taxing the money you would earn if you sold it even if you haven't sold it. This would be true of increased valuation on stocks, as well. As Biden has said many times, he doesn't want to increase taxes on those earning less than $400,000 per year.

"I think what's under consideration is a proposal that Senator Wyden and the Senate Finance Committee have been looking at that would impose a tax on unrealized capital gains, on liquid assets held by extremely wealthy individuals, billionaires. I wouldn't call that a wealth tax," Yellen told Tapper in a separate interview.

"But it would help get at capital gains, which are an extraordinarily large part of the incomes of the wealthiest individuals, and right now escape taxation, until they're realized, and often they're unrealized in the death benefit from a so-called step up of basis," she added.

Yellen emphasized that "it's not a wealth tax, but a tax on unrealized capital gains of exceptionally wealthy individuals."

The secretary of treasury's comments sparked backlash across social media on Sunday which had many point out its destructive economic effects.