NEW YORK, Aug 5 (Reuters) - The United States lost its top-notch AAA credit rating from Standard & Poor’s on Friday, in a dramatic reversal of fortune for the world’s largest economy.

S&P cut the long-term U.S. credit rating by one notch to AA-plus on concerns about growing budget deficits.

U.S. Treasuries, once undisputedly seen as the safest investment in the world, are now rated lower than bonds issued by countries such as the UK, Germany, France or Canada.

The outlook on the new U.S. credit rating is negative, S&P said in a statement, a sign that another downgrade is possible in the next 12 to 18 months. (Reporting by Walter Brandimarte; Editing by Jan Paschal)