The central bank has also expanded a key stimulus measure aimed at keeping long term interest rates low.

BBC: Japan shares up as G20 statement stokes weak yen hopes

One key Republican criticism of the stimulus plan is that many of its provisions would not jolt the economy back to life quickly enough.

CNN: Obama tells GOP no compromise on tax rebates

Market watchers said economic stimulus efforts in key nations will mean more demand, but gains are likely to be limited as traders watch to see whether easing measures in fact boost the economy as anticipated and whether China adds to the stimulus parade.

FORBES: Average Base Metals Prices Expected To Fare Better In Coming Quarters; Gains Seen As 'Moderate'