UBS has long been among most vocal cheerleaders for the integrated banking model combining investment banking and wealth management. But after more than $42bn of writedowns in its investment bank, Switzerland’s largest financial institution is publicly questioning that model. The big unknown is whether this will lead to a break-up.

The admission that investment banking and wealth management are not necessarily complementary businesses is a seismic shift for UBS. It also flies in the face of the integrated strategies that its peers are pursuing.