NEW YORK • "Tax us more!" is the message from about 20 super-wealthy Americans who have urged presidential candidates to back higher taxes on the wealthiest to confront climate change and other priorities.

"America has a moral, ethical and economic responsibility to tax our wealth more," said the group, which included investor George Soros, Facebook co-founder Chris Hughes, descendants of Walt Disney and the owners of the Hyatt hotel chain, in a letter on Monday.

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

The signers pointed out that fellow billionaire Warren Buffett has said he is taxed at a lower rate than his secretary.

The letter alluded to support among Democratic presidential candidates for higher taxes on the super wealthy, including Mr Pete Buttigieg and Mr Beto O'Rourke.

But it noted broad bipartisan support for taxing the super wealthy, saying "some ideas are too important for America to be part of only a few candidates' platforms".

It praised a proposal by Senator Elizabeth Warren that would raise taxes on those with more than US$50 million (S$68 million) in taxes, a measure expected to affect the 75,000 wealthiest families.

The letter was signed by 18 people representing 11 families, plus an anonymous person. Many in the group have been associated with progressive initiatives on issues such as climate change and the growing wealth gap.

Taxing the super wealthy "would slow the growing concentration of wealth that undermines the stability and integrity of our republic", the letter said.

Of about 40 countries, the United States is the sixth-highest in terms of wealth concentration, according to data from the Organisation for Economic Cooperation and Development.

AGENCE FRANCE-PRESSE