Big Swiss banks face major losses

Compared to last year, there has been no notable decrease in the level of risk at the big banks," the SBN annual report read.

The report added that the two banks would face “substantial losses relative to capital,” AFP reported on Thursday.

"The consequences of any misassessment of risks would be correspondingly severe," the SNB warned.

According to the report, while the banks' credit volumes have been almost untouched, credit quality in the United States and the Europe has stayed at low levels.

Meanwhile, the level of loss-absorbing capital of the big banks reached less than 2% of total assets at the end of 2010.

The central bank mainly blames the UBS for the climb in risks, asserting that it has raised its risk positions on its rading book.

However, the report underlines that the two big banks are not seiously affected by indebted eurozone countries.