The administration said Tuesday the event will be held Aug. 17 at the Treasury Department.

The financial overhaul signed by President Barack Obama didn't address their future, despite protests from Republicans that it was incomplete without a plan for the two companies. The Obama administration has said it wants to wait until next year to determine their future.

So far stabilizing the pair of mortgage buyers has cost taxpayers $145 billion.

The government created the two companies as a hybrid of a private company and a federal agency to help make mortgages available. They buy home loans from lenders, package them into bonds with a guarantee against default and sell them to investors.

They own or guarantee about half of all U.S. mortgages, or nearly 31 million home loans worth more than $5 trillion.

During the housing boom years, Fannie and Freddie faced political pressure to expand homeownership and competitive pressure from Wall Street to back ever-riskier loans. Defaults and foreclosures piled up. Two summers ago, the companies were in a desperate search to raise enough money to keep going. But it was too late, and the government had to take them over.

Speaking on "Meet the Press" on Sunday on NBC, Treasury Secretary Geithner said the administration's ultimate plan is likely to bring dramatic changes to the mortgage system.