Calls for a wealth tax have high support among Americans — including some ultra-wealthy Americans.

In an open letter to 2020 presidential candidates published Monday, a group of ultra-wealthy Americans including George Soros, Abigail Disney and members of the Pritzker and Gund families expressed their support for a moderate wealth tax on the 1%.

"America has a moral, ethical and economic responsibility to tax our wealth more," a copy of the letter published by The New York Times states.

As outlined in the letter, the signatories support the wealth tax for six reasons. Those include funding environmental initiatives and solving America's climate crisis; fueling economic growth; and providing funding for public health care. In addition, a wealth tax is fair, patriotic, and would strengthen our democracy by reducing inequality, according to the letter.

Read more: Elizabeth Warren's proposed wealth tax on the richest Americans won't remove the incentive to work, no matter what billionaires say

The letter's authors avoid endorsing a particular candidate but focus on the tax plan of Senator Elizabeth Warren. In that plan, wealthy families would not be taxed on their first $50 million worth of assets but would pay 2% on assets above the $50 million threshold and 3% on assets over $1 billion. Approximately 75,000 families would be impacted, according to the letter.

Warren's tax plan has the support of 74% of Americans, a 2019 survey published by The Hill found. A wealth tax also has the support of billionaire investor Warren Buffett. While not a signatory on the letter, Buffett penned an editorial for The New York Times in 2011 in support of a wealth tax.

The debate over how the wealthiest Americans should be taxed escalated in 2018 after President Trump's tax bill was widely criticized for benefiting the 1%. Business Insider previously reported that the top 1% of taxpayers — those making over $730,000 — would receive 20% of the total tax cut, according to the Tax Policy Center.

"Those of us in the richest 1/10 of the richest 1% should be proud to pay a bit more of our fortune forward to America's future," the letter says. "We'll be fine — taking on this tax is the least we can do to strengthen the country we love."