Federal Reserve Chairman Ben Bernanke signaled Monday that the Fed was likely to keep its stimulative policies in place despite improvements to the labor market. \"A wide range of indicators suggests that the job market has been improving, which is a welcome development indeed,\" the US central bank chief said in a speech on the outskirts of Washington. \"Still, conditions remain far from normal, as shown, for example, by the high level of long-term unemployment and the fact that jobs and hours worked remain well below pre-crisis peaks, even without adjusting for growth in the labor force.\" \"Moreover, we cannot yet be sure that the recent pace of improvement in the labor market will be sustained.\" For more than three years the Fed has maintained a rock-bottom interest rate and bought US bonds to force down long term rates, with the aim of getting growth back on a solid, sustainable base and bringing down the high rate of unemployment. Some analysts have speculated that with job creation numbers improving in recent months, the central bank could begin to tighten up its monetary policy even as early as the second half of this year. But Bernanke stressed the weakness of the recent gains and the need to keep up the Fed\'s current stance. \"Further significant improvements in the unemployment rate will likely require a more-rapid expansion of production and demand from consumers and businesses, a process that can be supported by continued accommodative policies.\"