Moody's Investor Service, the credit rating agency, will fire a warning shot at the US on Monday, saying that unless the country gets public finances into better shape than the Obama administration projects there would be "downward pressure" on its triple A credit rating. Examining the administration's outlook for the federal budget deficit, the agency said: "If such a trajectory were to materialise, there would at some point be downward pressure on the triple A rating of the federal government."