The European Central Bank returned from its four-week summer break today to review the latest economic data that analysts believe opens the room for an interest rate cut.
But in the absence of a clear policy signal from the ECB, markets see the outcome of ECB policymaking council's meeting as far from certain.
"The ECB decision is a close call . . . it won't be a sure-fire decision," said Citibank senior currency strategist Mr Steven Saywell.
Economists say out of three key sets of data, two - statistics showing both growth and inflation in the 12-nation euro zone slowing down - clearly back a case for lower rates.
Only euro zone M3 money supply, which the ECB sees as a harbinger of future inflation, does not fit the picture, staying well above the ECB's 4.5 per cent ceiling.
But economists dismissed the bigger-than-expected 6.4 per cent year-on-year jump in July M3 reported earlier this week. They are encouraged that the ECB played down the figures by saying they were inflated by special factors.
The majority view is that the central bank will trim its key 4.50 per cent lending rate by the end of September, helping to spur growth.
But several analysts believe the ECB will need more time to reach a consensus and prime the markets.
The 18-member ECB Governing Council will announce its rate decision at about 12.45 p.m.