The problem of inequality has become so pressing that it needs coordinated global action to address it, a group of over 500 economists and scientists said on Friday.

The group, which includes former Treasury Secretary and Federal Reserve Chair Janet Yellen along with French economist Thomas Piketty and Nobel Prize winner Daren Acemoglu, called in an open letter for the creation of a body akin to the UN’s Intergovernmental Panel on Climate Change (IPCC) to coordinate action against what it saw as disastrous effects on modern society.

“We are profoundly concerned, as they are, that extreme concentrations of wealth translate into undemocratic concentrations of power, unravelling trust in our societies and polarising our politics,” read the letter, referring to the findings of a G20 research committee led by noted American economist Joseph Stiglitz.

Just last week, shareholders of electric vehicle company Tesla voted to award the company’s CEO, Elon Musk, a pay package potentially worth $1 trillion, the largest in history. Musk, also the owner of social media platform X, is already the richest man in the world.

The IPCC has spearheaded the collection and dissemination of the scientific consensus on climate change over the past four decades and acted as a powerful force to push green policy forward. The economists said a new “International Panel on Inequality” would play a similar role, gathering evidence and pushing governments to act to tackle wealth gaps. 

The proposal was first contained in a recent report on inequality authored by a G20 research committee led by Stiglitz, who focused on inequality in his time as chief economist at the World Bank in the 1990s. The report found that between 2000 and 2024, the richest 1 percent of humanity had accumulated 41 percent of all new wealth — versus the 1 percent that had gone to the bottom half of the global population. That’s equal to an average gain of $1.3 million for the top 1 percent, versus $585 for people in the poorest half.

There have been marked political consequences of these large differences between the rich and the poor, with the report finding that countries with high levels of inequality were “seven times more likely to experience democratic decline than more equal countries.” 

Stiglitz said in an interview with POLITICO that the growing gap between rich and poor is evidence that the past four decades of middle-of-the-road governance on both sides of the Atlantic has failed. Populists across the West, including U.S. President Donald Trump, had seized the moment, playing on the grievances that failure had stoked, he said. 

“I do think that centrist politicians on both sides of the Atlantic bought into the neoliberal fantasy that if you had trade liberalization, financial liberalization, privatization, you would have more growth, and trickle-down economics would make sure that everyone would benefit,” said Stiglitz. 

He praised the recent victory of the Democratic Socialist mayor-elect of New York, Zohran Mamdani, who he said was addressing people’s everyday concerns, in contrast to politicians of both the center-left and center-right.

Mamdani, who last week surged to victory after defeating both Democratic rival Andrew Cuomo and Republican contender Curtis Sliwa, ran a strikingly effective media campaign centered on the city’s spiraling cost of living. His platform included promises to provide free bus travel, state-owned supermarkets and rent-controlled apartments.  

Stiglitz, who described himself as “very market friendly,” nonetheless said he thought the left-wing mayor had opened up space for debate.

“He’s saying things that are important to people: things like housing, food, transport, health care,” said Stiglitz. “He’s just ticking down the list of things that make for the necessities of a decent life, and he’s saying things aren’t working right.” 

Stiglitz won his Nobel Prize in 2001 for work on information asymmetries in markets, and served as a chief economist at the World Bank and as chair of the Council of Economic Advisers during former President Bill Clinton’s administration, where he had a famously rocky relationship with Treasury Secretary Larry Summers. With its embrace of globalization and the Internet revolution, Clinton’s team was hugely influential in drawing the parameters for the modern world economy.

The influential economist said that tackling inequality wasn’t just a moral choice, but a political necessity. He added that the yawning gap between the rich and poor was undermining the U.S. in its economic and technological competition with China.

“[The U.S.] won’t win if we are a divided society, a polarized society,” said Stiglitz, echoing rhetoric of the last Cold War. “The greatest weakness in the U.S. today is this division.”