Reuters/CNBC.com

Standard & Poor's on Monday downgraded the outlook for the United States to negative, saying it believes there's a risk U.S. policymakers may not reach agreement on how to address the country's long-term fiscal pressures.

"Because the U.S. has, relative to its 'AAA' peers, what we consider to be very large budget deficits and rising government indebtedness and the path to addressing these is not clear to us, we have revised our outlook on the long-term rating to negative from stable," the agency said in a statement.

The S&P said the move signals there's at least a one-in-three likelihood that it could lower its long-term rating on the United States within two years.

The U.S. dollar fell broadly on word of the revision. Gold prices, meanwhile, hit a new record above $1,496 an ounce.

"The headline has enough of a shock value. The initial reaction is that this is negative for dollar assets across the board." said Lou Brien, a market strategist with DRW Trading in Chicago.