Fannie Mae said yesterday it would draw another $15bn of funds from the US Treasury after a ninth consecutive quarterly loss - $19.8bn in the third quarter - drove its net worth below zero.

The loss at the government-run mortgage financier was largely due to $22bn of credit expenses as the company built its loss reserves against mounting mortgage defaults. Fannie also incurred losses from modifying the terms of mortgages for struggling borrowers under the government's housing market rescue plan.