Bernanke was referring to the Fed's unprecedented decisions last year to step in and financially back JPMorgan Chase & Co.'s takeover of then-troubled investment house Bear Stearns and throw its first of four financial lifelines to insurance giant American International Group Inc.
In remarks during a Fed conference in Charlotte, N.C., Bernanke said the central bank was forced to take action because the collapse of those companies would have dealt a serious blow to the financial system and the national economy.
The situation underscores the need for new powers to allow the government to safely wind down such huge firms, he said. Bernanke and Treasury Secretary Timothy Geithner recently asked Congress for such powers.
Since the financial crisis erupted in 2007, the Fed's balance sheet - its assets and liabilities
- has more than doubled to $2 trillion from $870 billion. Credit provided under those company bailouts accounts for only 5 percent of the Fed's current balance sheet, Bernanke said.
Still, "these operations have been extremely uncomfortable for the Federal Reserve to undertake and were carried out only because no reasonable alternative was available," he said.
Bernanke also signaled that the central bank is keeping a close eye on the size of commercial banks' reserve balances held at the Fed. If those balances aren't managed right, they could complicate the Fed's task of "raising short-term interest rates when the economy begins to recover or if inflation expectations were to begin to move higher," Bernanke said.
The Fed's radical programs to bust through the financial crisis and spur bank lending to consumers and businesses are helping. Its program to provide financial companies with loans, buy mounds of debt that companies rely on for short-terming financing of payrolls and supplies, and efforts to bolster consumer lending and the mutual funds have eased some credit stresses, he said.
Such efforts by the Fed, along with central banks in other countries, have "significantly reduced funding pressures for financial institutions, helped to reduce rates in bank funding markets and increase overall financial stability," Bernanke said.
Getting banks to boost lending to customers is a key ingredient to any economic turnaround. The Fed chief said he expects to see a "gradual resumption of sustainable economic growth." However, he didn't say when.