Dec. 15 (Bloomberg) -- Fannie Mae and Freddie Macâs federal regulator is renegotiating the companiesâ financing plan with the U.S. Treasury Department and may seek an increase to their $400 billion federal lifeline before the end of the year, according to people familiar with the talks. Treasury and Federal Housing Finance Agency officials are also debating whether to lower the cost of the companiesâ dividend payments on their borrowings from Treasury, according to these people, who requested not to be identified describing the internal deliberations. Fannie Mae and Freddie Mac, the largest sources of mortgage money in the U.S., have used $111.6 billion of their $400 billion in backup financing in less than a year. The companies say their 10 percent annual dividend payment, which comes to about $5 billion apiece, costs more than either have earned in most years and adds to their draws on Treasury. FHFA spokeswoman Stefanie Mullin, Treasury spokeswoman Meg Reilly, Freddie Mac spokesman Doug Duvall and Fannie Mae spokesman Brian Faith declined to comment. The financing plan instituted for Fannie Mae and Freddie Mac requires them to reduce their $1.57 trillion combined mortgage portfolios by 10 percent annually starting next year and caps their debt issuance at 120 percent of their assets. The Treasury and Federal Housing Finance Agency seized control of the mortgage-finance companies almost 16 months ago amid fears the two were at risk of failing. http://www.bloomberg.com/apps/news?pid=20601087&sid=aNmKaEXIGKTc&pos=3 There is enough TARP money out there to fill that hole...