The Treasury Department says it is increasing its funding commitment to Fannie Mae (FNM) and Freddie Mac (FRE).

Treasury said it was changing the preferred stock purchase agreements that were made to make sure each company maintains a positive net worth.

The agreements are being amended to $200 billion each from the original level of $100 billion each.

"The increased funding will provide forward-looking confidence in the mortgage market and enable Fannie Mae and Freddie Mac to carry out ambitious efforts to ensure mortgage affordability for responsible homeowners," Geithner said.

He said Treasury will continue buying Fannie Mae and Freddie Mac mortgage-backed securities to promote stability and liquidity in the market.

-By Jeff Bater, Dow Jones Newswires; 202-862-9249; jeff.bater@dowjones.com