Investors started to bet on a December rate hike this week after the accounts of the latest ECB meeting showed policymakers were preparing for a change in their message to reflect an improved economic outlook for the euro zone.

But Bundesbank President Jens Weidmann, normally one of the staunchest critics of the ECB's ultra-easy policy, played down the chance of an imminent change in rates.

"Regarding central bank rates in the euro zone, the imminent risk of a change is small for the moment," Weidmann told an audience in Rottach-Egern, Germany.

Weidmann repeated his view that the central bank should be winding down its 2.55 trillion euro ($3.10 trillion) bond-buying, stimulus programme more quickly.

But he stood by the ECB's pledge to keep rates at their current, record-low levels for long after the end of the purchases, which are scheduled to run at least until the end of September.

Investors have been bringing forward their expectations for their first ECB rate hike since 2011. Money markets are now pricing in a 70 percent chance of a 10 basis points increase in the deposit rate to -0.30 percent in December.

Such a negative deposit rate, effectively a charge banks pay on their idle cash, is one of a number of unconventional measures the ECB has taken since 2014 to stimulate lending and raise inflation back to its target of just under 2 percent.

With price growth now comfortably above 1 percent, Weidmann said banks should prepare for higher rates but cautioned that a return to the kind of monetary policy seen before the crisis would take time.

"The full normalisation of monetary policy will be a long path," he said.

(Reporting By Francesco Canepa; Editing by Balazs Koranyi)