The White House will ask the US Congress today to pass a new minimum tax on billionaires as part of a budget proposal intended to revitalise President Biden's domestic agenda and reduce the deficit.
The planned changes mean Tesla boss Elon Musk would need to pay an extra $50billion in tax, while Amazon founder Jeff Bezos would pay an additional $35billion, according to calculations for the Washington Post.
America's 700 billionaires are the target, but the proposals are also expected to catch tens of thousands more rich people as the plans would affect the top 0.01% of US households.
The tax would require that American households worth more than $100million pay a rate of at least 20% on their income as well as unrealized gains in the value of their liquid assets, such as stocks and bonds, which can accumulate value for years but are taxed only when they are sold.
The New York Times says Mr Biden's proposal to impose a tax on billionaires is the first time he has called for a type of wealth tax, technically a tax on an individual's untaxed investment gains.
While many in his party have advocated taxes that target an individual's wealth - not just income - Mr Biden has largely steered clear of such proposals in favour of increasing the top marginal income tax rate, imposing a higher tax on capital gains and estates and raising taxes on corporations.
Those already paying more than 20% would not owe any additional taxes, although those paying below that level would have to pay the difference between their current tax rate and the new 20% rate.
The idea of imposing a type of wealth tax has gained traction since Mr Biden was elected as Democrats have looked for ways to fund their sweeping climate and social policy agenda and ensure that the wealthiest Americans are paying their fair share.
Legal questions about such a tax also abound, particularly whether a tax on wealth - rather than income - is constitutional. If Congress approves a wealth tax, there has been speculation that rich Americans could mount a legal challenge to the effort.
Economists also warned that the US President's plans for a wealth tax could end up backfiring and trigger an exodus of firms from the country and encourage individuals to work fewer hours or retire earlier.