"In the long run, you will damage the independence of the central bank," Schauble said in Brussels in debate over giving the European Central Bank regulatory oversight over 6,000 eurozone banks.
Schauble also said one regulator for that many banks would be a Herculean task. "Nobody believes that any European institution will be capable to supervise 6,000 banks in Europe," Schauble said.
He also said it would be "very difficult," to persuade the German Parliament to go along with the plan, especially if it means giving up regulatory oversight for Germany's domestic savings banks, The New York Times reported.
Spain and France, however, support the initiative that was agreed to by eurozone leaders in June.
"If we are not able to deliver in the dates we have committed, this will not be neutral in terms of the stability of the markets," said Spanish Economy Minister Luis de Guindos.
French Finance Minister Pierre Moscovici said the new regulator was "essential to solve the euro crisis."
While Spain and France want to stay on schedule, German Chancellor Angela Merkel has reason to slow down creation of a new regulator, as it would require financial aid with Germany, as the eurozone's largest economy, paying the largest share, the Times said.
Germany has been shelling out the lion's share of the eurozone bailout funds that have gone to Greece, Portugal and Ireland, and asking Berlin to pay more could be detrimental to Merkel's 2013 re-election campaign.