US mortgage finance firm Fannie Mae has asked for another $15bn (£9bn) in state aid after announcing losses of $19bn between July and September.
The losses stemmed from the increased costs of buying up bad mortgage-backed loans as part of the government's efforts to support the housing market.
This is the fourth time that the firm has requested state aid.
Both Fannie Mae and fellow mortgage giant Freddie Mac were taken under government control last year.
Fannie's latest request takes the amount that the pair have requested from the US Treasury to more than $100bn.
It said it would use additional government aid to cover future losses on bad mortgage loans, as well as helping to cover its third-quarter losses.
Fannie Mae and Freddie Mac buy mortgages from approved lenders then sell them to investors. Together, they underwrite more than half of all US mortgages, worth more than $5 trillion.
The firms hit difficulty after lowering their lending criteria for borrowers during the housing boom.
Under a rescue plan passed by Congress in July last year, the US government gained the right to provide unlimited liquidity to the two companies and to buy their shares, to prevent them from collapsing.
Next year, the US government will unveil its plans for the two mortgage giants.
According to some analysts, its options are limited.
"It appears evident that they will remain under [government control] indefinitely," said Rajiv Setia at Barclays Capital in New York.
"There is no way to privatise them in this environment. It could actually be a full decade before something like that happens."