Federal Open Market Committee, in a 7-to-3 vote, opted to keep rates steady in what Chairwoman Janet Yellen described as a "new normal" as central banks elsewhere around the globe embark upon quantitative-easing measures. Yellen also said she is "pleased with" the health of the economy.

The US dollar fell after the Federal Reserve left interest rates unchanged, but signaled that it may tighten monetary policy in the coming months.

However, there are contradictions among the FOMC members. One group is in favor of an immediate rate hike, while the other sees no need to tighten monetary policy later this year.

"The Fed noted the emergence of more powerful arguments in favor of raising rates, but decided to wait until new evidence of further progress in achieving these goals,"