US Federal Reserve keeps its federal fund rate unchanged after concluding its two day meeting. Chair Janet Yellen said that the possibility of Brexit was one of the factors that led the US Federal Reserve to keep interest rates on hold. The US central bank also said it expected a slower path for future rate rises. The Fed raised its target range for the federal funds rate to 0.25 percent to 0.5 percent in December last year, the first rate hike in nearly a decade.In yesterday's statement, Fed officials gave a mixed assessment about the US economy, saying that the labor market has slowed its improvement pace, while growth in economic activity appeared to have picked up since April. The Fed officials also lowered their forecast for GDP growth in 2016 to 2 percent from its March forecast of 2.2 percent.