The so-called wealth tax is a politically divisive economic policy, but one that is regaining attention amid rising inequality and shifting demographics.
It follows an earlier G20 meeting, in which finance leaders explored plans for a global minimum tax on the world's 3,000 billionaires.
Colombia, Scotland and the U.S. have all proposed wealth taxes in recent years, joining the likes of Switzerland, Norway and Spain in imposing taxes specifically on the super-rich.
And even some of the world's wealthy are backing such calls.
But can such a policy work in reality, and is it likely to take hold?
Persons:
Joe Biden, Phil White
Organizations:
U.S, Patriotic Millionaires, CNBC
Locations:
Colombia, Scotland, Switzerland, Norway, Spain