Aiming to bolster the US economy's defences against a financial contagion that has spread around the globe, the Federal Reserve is expected to trim interest rates this week for the third time in less than two months.

Analysts said the urgency for the Fed to move had diminished over the past few weeks as turbulent financial markets have calmed down and the US economy has shown some surprising resilience.

Still, most said a rate cut was the most likely outcome of the Fed's policy meeting tomorrow because it would reinforce the recent positive developments and help to ensure that the eight-year US economic expansion remains firmly on track.