US Federal Reserve Chairman Ben Bernanke told Congress on Tuesday that the central bank's efforts have helped ease the credit market strains.

"Notably, our lending to financial institutions, together with actions taken by other agencies, has helped to relax the severe liquidity strains," said Bernanke in testimony to the House Financial Services Committee.

He said the Federal Reserve has responded forcefully to the financial and economic crisis since its emergence in the summer of 2007, adding "the past 18 months or so have been extraordinarily challenging for policymakers around the globe, not least for central banks."

Earlier Tuesday, Federal Reserve said it is prepared to expand a key program to one trillion dollars to get the frozen credit markets functioning again.

"The expansion could increase the size of the Term Asset-Backed Securities Loan Facility (TALF) to as much as US$1 trillion and could broaden the eligible collateral to encompass other types of newly issued AAA-rated asset-backed securities," said a statement released by the US central bank.

Those AAA-rated securities include commercial mortgage-backed securities, private-label residential mortgage-backed securities, and other asset-backed securities, it said.

(Xinhua News Agency February 11, 2009)