More than 1,500 academics and economists called on global leaders to join an initiative against extreme inequality, the Guardian reported Friday.

Academics and economists from over 100 countries signed an open letter backing the International Panel on Inequality (IPI) ahead of the upcoming U.N. General Assembly and urged global leaders to join the initiative.

They described the growing gap between the richest and the poorest as "a policy choice that can be reversed."

High-profile signatories include former U.S. Treasury Secretary Janet Yellen, Nobel Prize winner Daron Acemoglu and several other prominent economists, including Thomas Piketty, Mariana Mazzucato and Jayati Ghosh.

"Extreme concentrations of income and wealth translate into undemocratic concentrations of power, unravelling trust in our societies and polarizing our politics," they said in the letter.

Established with the support of Spain, South Africa, Brazil, Norway and championed by U.N. Secretary-General Antonio Guterres, the IPI is expected to be chaired by Nobel Prize-winning economist Joseph Stiglitz, who said he hoped it would become "the world’s leading authority on the issue.”

"It is news to no one that the gap between the richest and the poorest in most countries is large and growing. The interrelated impacts of the inequality crisis are affecting the lives of many, with significant political, economic, social and environmental consequences playing out across the globe,” Stiglitz reportedly said.

The letter’s signatories say the IPI could help establish a "shared scientific consensus” on the nature and extent of global inequality while identifying potential policy solutions.

Experts also raised concerns over both the widening gap between wealthy and poorer countries and inequalities within individual economies.