The three billionaires are sitting on a combined $248.5 billion fortune, which outstrips the combined net worth of an estimated 160 million Americans, or 53 million US households. The study entitled Billionaire Bonanza 2017 was compiled by the Institute for Policy Studies.

“So much money concentrating in so few hands while so many people struggle is not just bad economics, it’s a moral crisis,” said Josh Hoxie, the report's co-author.

The 400 richest people in the US have a combined $2.68 trillion wealth, more than the gross domestic product (GDP) of the United Kingdom, France or India.

“Our wealthiest 400 now have more wealth combined than the bottom 64 percent of the US population, an estimated 80 million households or 204 million people. That’s more people than the population of Canada and Mexico combined,” the report says.

Tax cuts, proposed by US President Donald Trump, are likely to widen the gap, according to the findings, as 80 percent of the tax relief would benefit only the wealthiest one percent of households.

“Wealth inequality is on the rise. Now is the time for actions that reduce inequality, not tax cuts for the very wealthy,” said the co-author of the report Chuck Collins.

The study suggests two ways of narrowing the wealth gap.

“First, we must not make inequality worse through new tax cuts for the wealthy. The proposed Trump tax cuts, as currently designed, would grow top one percent fortunes and do little to reduce the ranks of America’s “underwater nation.”

The second way is to implement policies to reduce concentrated wealth, the report suggests.

”Inequality will continue to widen unless we intervene directly to reduce grand concentrations of private wealth. By taxing our wealthiest households, we could raise significant revenues and then invest these funds to expand wealth-building opportunities across the economy.”