U.S. consumer prices were flat in December, pointing to muted inflation pressures that should help give the Federal Reserve room to prop up the economy by staying on its ultra-easy monetary policy path.

The Labor Department said on Wednesday its Consumer Price Index was unchanged last month, held back by a drop in gasoline prices. The reading was in line with analysts' expectations in a Reuters poll.

Last month, the Fed said it would keep interest rates near zero at least until the jobless rate falls to 6.5 percent, as long as the central bank believes inflation will stay below 2.5 percent.

Wednesday's data will likely reinforce the view that inflation will not hit the Fed's threshold anytime soon.

To boost growth and get Americans back to work in the wake of the Great Recession, the Fed has kept interest rates near zero since late 2008 and has bought some $2.5 trillion in assets.