The U.S. Federal Reserve must limit the long-term effects of the coronavirus, Ben Bernanke and Janet Yellen write in an op-ed for the Financial Times.

The former chairs said the Fed has a “useful role to play” and that fiscal policy will have “to do more” as the impact of the virus becomes apparent, the FT reported.

The central bank “must ensure that the economic damage from the pandemic is not long-lasting.” It should also ensure that credit is available for otherwise sound borrowers, who face temporary issues, Bernanke and Yellen said.

In the essay, the two say the Fed should look for more authority that would give it the power to purchase corporate bonds on top of the Treasurys and mortgage-backed securities it already plans to buy.

“The Fed’s intervention could help restart that part of the corporate debt market, which is under significant stress,” Bernanke and Yellen wrote. “Such a program would have to be carefully calibrated to minimize the credit risk taken by the Fed while still providing needed liquidity to an essential market.”

(This report uses material from the AP, Bloomberg and Reuters.)

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