The European Central Bank will become the main supervisor for Euro zone banks under plans for a banking union to be detailed on September 12. The European Commission's proposal is part of wider efforts to prevent problems at banks struggling with bad debts. Following are some of the proposals, and problems still to be solved
Problems: What to do with Britain, the EU's biggest financial centre, which has said it will stay outside the union. Will European Union treaty changes later be needed for more ambitious aspects of a complete banking union? (Click on graphic)