UPDATE 2-S&P says GSEs may pose risk to US government rating

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NEW YORK, April 14 (Reuters) - Standard & Poor's Ratings Services said on Monday that the risks the government-sponsored enterprises, or GSEs, pose to the U.S. government's triple-A debt rating are far greater than those posed by broker-dealers.

In a deep and prolonged recession, the maximum potential cost of assisting the GSEs, together with loans and guarantees extended by U.S. government agencies, yields a potential fiscal cost to the government of up to 10 percent of GDP, S&P said in a statement.

The recent rescue of ailing Bear Stearns BSC.N highlighted the potential risks associated with supporting the broker-dealer segment of the U.S. financial system, S&P said, adding that the GSEs pose a far greater fiscal risk to the government's rating.

The maximum potential cost of assisting the broker-dealer sector remains small relative to the size of the economy, at below 3 percent of GDP, S&P said.

A U.S. Treasury spokeswoman declined to comment on the S&P report.

Fannie Mae (FNM.N: Quote, Profile, Research) and Freddie Mac (FRE.N: Quote, Profile, Research) are shareholder-owned, GSEs charged by Congress with supporting the housing sector by keeping money flowing in the mortgage market.

To do this, they sell debt and use the proceeds to buy mortgages from lenders, which then gives lenders the funds to make more loans. The loans are then repackaged into securities for sale to investors.

Fannie Mae and Freddie Mac also hold loans and securities in their portfolios, which are monitored by a federal regulator.