A group of ultrarich Americans wants to pay more in taxes, saying the nation has a “moral, ethical and economic responsibility” to ensure that they do.

In an open letter addressed to the 2020 presidential candidates and published Monday on Medium, the 18 signatories urged political leaders to support a wealth tax on the richest one-tenth of the richest 1 percent of Americans. “On us,” they wrote.

“The next dollar of new tax revenue should come from the most financially fortunate, not from middle-income and lower-income Americans.”

Such a tax could “help address the climate crisis, improve the economy, improve health outcomes, fairly create opportunity, and strengthen our democratic freedoms,” the letter said. “Instituting a wealth tax is in the interest of our republic.”

Among the billionaires and multimillionaires who signed the letter were Abigail Disney, the independent filmmaker, activist and heir to the Disney entertainment empire; Facebook co-founder Chris Hughes; investor and liberal political donor George Soros; and Regan Pritzker, board chair of the Libra Foundation.

The letter, which emphasized that it was nonpartisan and not to be interpreted as an endorsement of anyone in 2020, noted that several presidential candidates, including Sen. Elizabeth Warren (D-Mass.), Pete Buttigieg and Beto O’Rourke, have already signaled interest in addressing the nation’s staggering wealth inequality through taxation.

Warren’s proposal, the letter writers said, would implement a tax of 2 cents on the dollar on assets over $50 million and an additional 1 cent tax on every dollar of assets over $1 billion. It would generate nearly $3 trillion in tax revenue over 10 years, they said.

Recent polls show there’s an appetite for increasing taxes on the wealthy.

An April Quinnipiac poll found 60 percent of voters supported an annual tax which would tax individuals 2 percent on any wealth over $50 million, while 59 percent opposed raising the tax rate to 70 percent on individual income over $10 million.

During the first year of his administration, President Trump signed a sweeping overhaul of the U.S. tax code. While Republicans cast it as a boon to the middle class, lower- and middle-income taxpayers saw only moderate tax relief while the highest earners received a substantial windfall. According to the nonpartisan Tax Policy Center, the tax law will give the richest 1 percent of Americans — those earning more than $732,800 a year — an average tax break on personal income of about $33,000. Those on the opposite end of the spectrum — those earning less than $25,000 annually — saw an average personal income tax break of $40.

The richest 0.1 percent of Americans now command more wealth than the bottom 80 percent, according to a recent working paper on wealth inequality by Gabriel Zucman, an economist at the University of California at Berkeley. Nearly 20 percent of the nation’s wealth belongs to the country’s richest people.

Among the people who signed the open letter are activists and philanthropists known for their work on social and political issues. Earlier this year, Disney criticized The Walt Disney Co. in an op-ed in The Washington Post, calling attention to chief executive Bob Iger’s compensation last year of $65 million, which amounts to more than 1,400 times the median pay of a Disney worker.

The letter is also signed by Louise J. Bowditch, Robert S. Bowditch, Sean Eldridge, Stephen R. English, Agnes Gund, Catherine Gund, Nick Hanauer, Arnold Hiatt, Molly Munger, Justin Rosenstein, Stephen M. Silberstein, Ian T. Simmons, Liesel Pritzker Simmons, Alexander Soros and Anonymous.