Democratic Sens. Elizabeth Warren (D-Mass.) and Jack Reed (D-R.I.) sent a letter Tuesday to the Treasury Department's Office of Financial Research (OFR) expressing concern about the office's failure to use its authority to safeguard the financial system in the wake of last month's bank failures. "As OFR identifies ongoing and emerging sources of risk where regulators lack visibility, we urge the OFR to take additional steps to fill these data gaps," the senators wrote in a letter obtained exclusively by Yahoo Finance. "Recent turmoil in the banking system following the failures of Silicon Valley Bank and Signature Bank, which forced financial regulators to take extraordinary action to stem contagion, underscores the need for OFR to use all its tools to live up to its mission and help keep our financial system safe." Last month, Treasury Secretary Janet Yellen, with a unanimous recommendation from the Fed and the FDIC, approved systemic risk exceptions for the failures of SVB and Signature, enabling the FDIC to guarantee all of the deposits of both banks given that it appeared that contagion from SVB's failure could be far-reaching and cause damage to the broader banking system. The senators sent their letter ahead of economist Ron Borzekowski's nomination hearing Tuesday before the Senate Banking Committee to serve as director of the OFR.