A group of German professors has filed a complaint to the country's highest court against the European Union's plans to create a so-called banking union, a central part of the effort to make the continent's financial system more resilient.

The Federal Constitutional Court said Monday it had received the complaint. It wasn't clear when the court might rule; verdicts on previous attempts to block measures meant to stem Europe's debt crisis took at least several months.

The group behind the complaint says the banking union "has no legal basis in the European treaties."

It objects to handing the European Central Bank direct supervision of the eurozone's biggest lenders with binding powers over national authorities, and opposes plans for a separate authority with the power to dissolve or restructure failing banks.