Fitch Ratings on Monday revised to negative the outlook on the United States' AAA credit rating after a Congress committee failed last week to agree on at least $1.2 trillion (774 billion pounds) in deficit-reduction measures.

The negative outlook reflects Fitch's declining confidence that timely fiscal measures necessary to place U.S. public finances on a sustainable path and secure the U.S. AAA sovereign rating will be forthcoming, the ratings agency said in a statement.

The so-called 'super committee' six Democrats and six Republicans failed last week to reach an agreement on deficit reduction. It said at the time it could cut the outlook, but that a downgrade was only an outside possibility.

The committee abandoned its efforts, setting in motion automatic cuts that would result in lowering the deficit by $1.2 trillion over 10 years. The cuts are designed to be split evenly between domestic and military programs.

(Reporting by Walter Brandimarte; Editing by Diane Craft)