The future of Fannie Mae and Freddie Mac, the two government-controlled entities that guarantee around 60 percent of the U.S. mortgage market, remains uncertain, but their federal regulator is requesting a plan to wind them down and sell their assets.

Bloomberg reported that the Federal Housing Finance Agency has hired the accounting and consulting firm PricewaterhouseCoopers to develop a receivership plan by Oct. 1. A spokeswoman for the FHFA told Bloomberg the move was part of ordinary regulatory activities and did not imply that regulators are contemplating receivership.

Congress mandated the creation of Fannie Mae during the Great Depression and later created Freddie Mac in 1970, and the next step for the two entities is ultimately up to legislators. But while some officials, such as Sen. Johnny Isakson, R-Ga., have proposed plans to wind down the agencies, housing experts widely believe that nothing will be done until after the presidential election.

The issue remains politically complex: Fannie and Freddie were taken over by the government during the 2008 crisis and forced to pay a preferred dividend to the U.S. Treasury each quarter. But as their portfolios deteriorated, Fannie and Freddie began bleeding cash and now owe the government around $190 billion, sparking outrage from taxpayers and politicians alike. Yet despite their much-diminished financial positions, the two entities have become critical in propping up the housing market by buying and guaranteeing mortgages by private lenders.

A study by the Center for Data Analysis released in June concludes that the removal of Fannie and Freddie would have a minimal impact on home ownership levels, but they currently provide a linchpin in the mortgage market. A winddown of their enormous portfolios probably would take years.