The U.S. government-controlled company continued to see a dramatic surge of borrowers fall behind as the unemployment rate climbs. At the end of October, about 4.7 per cent of Fannie Mae's borrowers had missed at least three payments. That's nearly triple last year's level.

Seized by federal regulators 14 months ago, the problems at Fannie Mae and sibling company Freddie Mac have proven far worse than most experts had foreseen. Fannie Mae's request will bring the tab for rescuing both companies to about $111 billion. The government has promised up to $400 billion in assistance.

And Fannie Mae cautioned: "We do not expect to operate profitably in the foreseeable future.''

Fannie Mae posted a quarterly loss of $19.76 billion, or $3.47 per share. The loss includes $883 million in dividends paid to the Treasury Department and compares with a loss of $29.41 billion, or $13 per share, in the year-ago period.

The results were driven by $22 billion in credit losses as the company continued to build its reserves for sour mortgages.

The latest request for financial aid - Fannie Mae's fourth - brings the company's total to about $60 billion.