USEC Inc. has spent $1.5 billion developing the plant in Piketon, Ohio about 65 miles south of Columbus. The total cost was pegged at $3.5 billion. The company said in June that without the guarantee, it wouldn't be able to obtain private loans.
USEC spokeswoman Elizabeth Stuckle said Tuesday the company would try to find other financing, but that would be difficult in the current economic environment.