The odds are that the U.S. will slip into a recession, but the depth of the economic downturn will hinge on where housing prices go and the level of mortgage defaults, said Martin Feldstein, a Harvard University professor and president of the National Bureau of Economic Research.

Martin Feldstein

In an interview on CNBC, Feldstein said the chances of a recession have decreased in the past month, but "the odds are we will slide into a recession."