WASHINGTON — In the wake of the severe conditions in the housing market, the Senate late Friday passed a measure aimed at providing relief to those affected by the subprime crisis in part by expanding the availability of government-insured mortgages.

The bill, which passed 63-5, would create an affordable housing fund, paid for by Fannie Mae and Freddie Mac. The fund would provide $500 million for foreclosure rescues in the first year. The measure also tightens regulations of Fannie and Freddie, the main purchasers of mortgages from credit unions. It creates a new regulatory entity, the Federal Housing Finance Agency.

The House passed a similar bill earlier this year and the two chambers hope to reconcile the versions and get a bill to President Bush later this week. The Bush administration is hoping that the measure will include the proposal unveiled Sunday by Treasury Secretary Henry S. Paulson to give his department the power to buy stock and make loans to Fannie and Freddie, which have lost considerable money in the last year.