(Reuters) - Fitch Ratings on Wednesday reiterated the high and rising U.S. federal and government debt burden was not consistent with keeping its AAA credit rating, but said no decision on whether to cut the top level rating is likely to come before 2013.

Federal debt will rise in the absence of expenditure and tax reforms that would address the challenges of rising health and social security spending as the population ages, Fitch said in a statement.

The high and rising federal and general government debt burden is not consistent with the U.S. retaining its 'AAA' status despite its other fundamental sovereign credit strengths, the firm said.