Fed keeps rates unchanged, maintains rate pledge (by Steve Goldstein)

WASHINGTON (MarketWatch) -- While flagging concerns with global growth for the first time, the Federal Reserve on Tuesday decided to keep interest rates unchanged. The Fed also made no alterations to its policy of selling short-term holdings and reinvesting them into longer-term securities and reiterated its pledge to keep rates at low levels through the middle of 2013. On the third anniversary of targeting the Fed funds rate at a level between 0% and 0.25%, the Fed said the "economy has been expanding moderately, notwithstanding some apparent slowing in global growth." The Fed also made no mention of altering its communication strategy, a hot topic of recent speeches by central bank officials. As with the last meeting, the Fed voted 9-to-1 in favor, with Chicago Fed President Charles Evans dissenting as he called for additional policy accommodation.