Standard & Poor’s has downgraded the United States' AAA credit rating, Bloomberg reports.

S&P lowered the US one level to AA+ while slamming the US political process and criticizing lawmakers for failing to cut spending or raise revenue sufficiently to reduce record budget deficits.
In addition, S&P kept its outlook on the US economy at "negative", expressing reduced confidence Congress will end Bush-era tax cuts or tackle entitlements. 
“The downgrade reflects our opinion that the fiscal consolidation plan that Congress and the Administration recently agreed to falls short of what, in our view, would be necessary to stabilize the government’s medium-term debt dynamics,” S&P said in a statement late yesterday after markets closed.
The rating could be cut to AA within two years if spending reductions are lower than agreed to, interest rates rise, or “new fiscal pressures” result in higher general government debt, the firm added.
Lawmakers agreed Aug. 2 to raise the nation’s $14.3 trillion debt ceiling and put in place a plan to enforce $2.4 trillion in spending reductions over the next 10 years, less than the $4 trillion S&P had said it preferred. 
US Response
The U.S. immediately lashed out at S&P after the downgrade, with a Treasury Department spokesman saying the firm’s analysis contains a $2 trillion error. The spokesman, who asked not to be identified by name, didn’t elaborate, saying the mistake speaks for itself.
Moody’s Investors Service and Fitch Ratings affirmed their AAA credit ratings on Aug. 2, the day President Barack Obama signed a bill that ended the debt-ceiling impasse that pushed the Treasury to the edge of default. 
Moody’s and Fitch, however, did say a failure on the part of US lawmakers to enact debt reduction measures could lead to credit rating downgrades from their firms as well if the economy weakens. 
A US credit-rating cut would likely raise the nation’s borrowing costs by increasing Treasury yields by 60 basis points to 70 basis points over the “medium term,” JPMorgan’s Terry Belton said on a July 26 conference call hosted by the Securities Industry and Financial Markets Association.
“That impact on Treasury rates is significant,” Belton, global head of fixed-income strategy at JPMorgan, said during the call. “That $100 billion a year is money being used for higher interest rates and that’s money being taken away from other goods and services.”
Remaining AAAs
S&P gives 18 sovereign entities its top ranking, including Australia, Hong Kong and the Isle of Man, according to a July report. The UK  which is estimated to have debt to GDP this year of 80 percent, 6 percentage points higher than the U.S., also has the top credit grade. In contrast with the U.S., its net public debt is forecast to decline either before or by 2015, S&P said in the statement yesterday.
New Zealand is the only country other than the U.S. that has a AA+ rating from S&P and an Aaa grade from Moody’s. Belgium has an equivalent AA+ grade from S&P, Moody’s and Fitch.