The US Federal Reserve is ready to take steps to lift the US economy if it weakens.
Chairman Ben Bernanke told Congress that international pressures, such as the eurozone crisis, pose real risks for the US economy and the fed is prepared to take action.
But he gave few hints of any change to policy soon.
His tone was in contrast to remarks made in a speech late on Wednesday by vice chairman Janet Yellen, who listed weaknesses in the US economy and appeared to lay out the case for further support by the Federal Reserve.
The BBC reports her list included continuing housing problems and a weak jobs market.
Mr Bernanke said on Thursday the Fed was closely monitoring "significant risks" to the United States from Europe's debt crisis, but said that "despite economic difficulties in Europe, the demand for US exports has held up well".
He said employment growth was one of the key issues he and the rest of the Fed's Open Markets' Committee, which meets regularly to decide on monetary policy, would be looking at in the next meeting.
Mr Bernanke also said he expected inflation to stay at or slightly below the 2% target.