The White House on Thursday urged Congress to extend jobless aid for unemployed Americans and warned that failure to act could inflict a heavy toll on the U.S. economy.

"Without extended benefits, the country would have had 800,000 fewer jobs as of September 2010, and failure to act to extend benefits again could cost the nation 600,000 jobs by the end of next year," according to a new report from the White House Council of Economic Advisers.