The head of German banking giant Commerzbank (OTC: CRZBY) says that there are more rough seas ahead for the banking industry, particularly in the US. "Bankers did not adequately understand these (mortgage) investments and relied too heavily on high-grade credit ratings from agencies that helped put together the products, then rated them," Klaus-Peter Müller told The New York Times. "This ignorance of the risks extended to the top echelons of the banks."

Not a very pleasant way to talk about your peers, but probably accurate nonetheless.

Commerzbank has already admitted to $1.8 billion in subprime exposure, but Müller fears that US banks are being selective in their disclosures in the hopes that some of the problems will go away. He is also concerned that US banks used the opinions of ratings agencies to make investment decisions instead of doing their own risk management.

In general, Müller is probably right. If his hint about US banks being slow in disclosing problems is true, he may feel that there is another shoe to drop in the form of more big write-offs before the end of the year.

That would put much more pressure on banking stocks.

Douglas A. McIntyre is an editor at 247wallst.com.