US Federal Reserve chairman Ben Bernanke says the United States cannot fully recover from the recession until employers start hiring more workers.
In an address to the National Press Club, Dr Bernanke said the economy was strengthening and would likely grow more quickly this year as more confident consumers and companies spend more.
But he warned it could still take several years for unemployment to return to more normal levels.
"Until we see a sustained period of stronger job creation, we cannot consider the recovery to be truly established," he said.
The ABC reports the comments suggest the Federal Reserve will stick with its programme to prime the economy by purchasing $US600 billion worth of Treasury bonds by mid-year.
The Department of Labor says unemployment in the fell in January to 9% from 9.4% a month earlier.
The BBC reports it was the second such monthly fall, after unemployment fell from a rate of 9.8% in November.
But despite this, the number of jobs created, 36,000, was far below the expected 140,000.