The US Federal Reserve is expected to take note of an improving economy at the close of a meeting, while cautioning that high unemployment puts the recovery at risk.

The Fed is widely expected to hold overnight lending rates at close to zero percent and repeat its intention to keep rates exceptionally low for an extended period in a statement the Fed will issue around 2:15 p.m. EDT, after the central bank's two-day policy meeting draws to a close.

It is also expected to keep its massive financial support for the economy in place, although it may offer a suggestion of how it plans to withdraw that underpinning.