"We have been encouraged by the responses to these programs," Bernanke said in testimony to the House of Representatives Financial Services Committee.

Bernanke defended the Fed's actions to lawmakers who worried that the US central bank had overstepped with lending programs, which have flooded financial markets with money, in an effort to pull the financial sector out of the deepest crisis since the Great Depression.

Aggressive responses by the Fed and other central banks to the financial crisis of the last 18 months have helped reduce interbank lending rates internationally and taken some of the steam out of liquidity pressures at the end of 2008, he said.

Lawmakers at the hearing expressed concern about the Fed's use of emergency powers and disclosure of information surrounding special lending facilities.

"Going forward ... it does not seem healthy to me in our democracy for the amount of power that is now lodged in the Federal Reserve with very few restrictions to continue," Committee Chairman Barney Frank said.

However, Frank, a Massachusetts Democrat, added he believes the Fed has used its authority responsibly in the crisis.

Fed officials are considering providing the public with more information about the central bank's balance sheet and lending policies, Bernanke said.

The Fed has more than doubled its balance sheet to greater than $1.8 trillion since the middle of last year as it has pumped money into the financial system and propped up failing institutions.

Bernanke acknowledged the expansion of the Fed's balance sheet could expose the economy to inflation risks if the central bank fails to withdraw liquidity measures when the economy recovers. Policy-makers were paying close attention in an effort to minimize that risk, he said.