WASHINGTON -- The chairman of the House Financial Services Committee confirmed Saturday that the government is planning to intervene to stabilize mortgage giants Fannie Mae and Freddie Mac.

But Rep. Barney Frank (D-Mass.) said he doesn't know the details of what's planned. He said Treasury Secretary Henry Paulson "intends to use the powers that Congress provided" in a law passed in July to keep the companies going. CNN.com reported that the Paulson is expected to announce his plan Sunday. In July, CNN.com reported, Paulson asked Congress for the right to use taxpayer funds to intervene in Fannie's and Freddie's affairs, but hoped the pledge alone would be sufficient.

"If you have a bazooka in your pocket and people know it, you probably won't have to use it,'' he said at a July 15 Senate Banking Committee hearing.

A person briefed on the matter said the government is planning to take over both companies, which together hold or back half of the nation's mortgage debt.

The source said the deal, which could cost taxpayers billions, is expected to include the departure of the CEOs of both companies.