The FSOC focused on climate for the first time since Congress established the body in 2010.

The Financial Stability Oversight Council held its first public meeting under Treasury secretary Janet Yellen’s leadership Wednesday. | Alex Wong/Getty Images

Treasury Secretary Janet Yellen on Wednesday called climate change “an existential threat” and the biggest emerging risk to the health of the U.S. financial system, pledging to marshal regulatory forces to guard against its harmful effects.

Yellen made the promise during her inaugural appearance as the head of the Financial Stability Oversight Council, a panel of top regulators tasked with policing Wall Street behavior that has the potential to crash the entire economy.