"The crisis in Europe presents a very significant risk to global recovery," Geithner said at a hearing of the Senate Banking Committee. "Europe is so large and so closely integrated with the U.S. and world economies that a severe crisis in Europe could cause significant damage by undermining confidence and weakening demand."

Geithner told lawmakers that the crisis was slowing economic growth in Europe, which represents a threat to the US economy.

"We want Europe to move and we want to make sure they move more aggressively," Geithner said.

The secretary urged European leaders to move more quickly to build up rescue funds to give nervous financial markets greater assurances that they have the resources to prevent a default by a European nation from jolting the global financial system.

He also called for legislators to pass US President Barack Obama's job plan to boost the US economy.