(Fox News) – Credit rating agency Standard & Poor’s says it has downgraded the United States’ credit rating for the first time in the history of the ratings.

The credit rating agency says that it is cutting the country’s top AAA rating by one notch to AA-plus. The credit agency said late Friday that it is making the move because the deficit reduction plan passed by Congress on Tuesday did not go far enough to stabilize the country’s debt situation.

A source familiar with the discussions said that the Obama administration believes S&P’s analysis contained “deep and fundamental flaws.”