US Federal Reserve Chairman Ben Bernanke told Congress yesterday that a prolonged rise in oil prices would pose a danger to the United States economy.

But he said a more likely outcome is a temporary and modest increase in consumer prices - not runaway inflation.

Bernanke expressed confidence that US economic growth would increase this year. But he warned it won't be strong enough to quickly lower unemployment, now at 9 percent.

He also cited other risks to the economy, including rising prices for oil, gasoline, food and other commodities, and further weakness in home prices. All could prompt Americans to spend less.

The Fed chief said the economy still needs the support of its US$600 billion bond-purchase program, downplaying runaway inflation risks that others have raised.