The US Congress approved a massive housing market rescue bill on Saturday, offering emergency financing to mortgage titans Fannie Mae and Freddie Mac, and setting up a $300-billion fund to help hundreds of thousands of troubled homeowners.

Approved by the Senate in a 72-13 vote, the election-year rescue bill was passed by the House of Representatives on Wednesday. President George W. Bush was expected to sign it promptly, amid doubts about how much it would help.

With foreclosures at record levels, home sales sluggish and property values down, the US is in its deepest housing slump since the Great Depression.

Fears that Fannie Mae and Freddie Mac, the largest US mortgage companies, might collapse rattled global markets earlier this month and led the Bush administration to call for emergency measures to bolster investor confidence.

They recently lost billions of dollars on bad home loans and the stock market has whipsawed their share prices on uncertainty about whether they have enough capital.

Housing activists and scholars said this election-year bill will ease, but not end, the housing crisis. "We have a housing market going into cardiac arrest. This bill is like CPR to stabilize the situation," said David Abromowitz, a senior fellow at the Center for American Progress, a think tank in Washington.

The National Community Reinvestment Coalition, an alliance of 600 community investment and development groups, estimated 2.5 million US households will face foreclosure this year.

While Congress' legislation is welcomed, the coalition said, it "will likely have little effect on the foreclosure crisis gripping the financial markets and economy."