He also acknowledged the Swiss bank had made mistakes.
'We judged the market too favourably in 2009', he said, in an implicit criticism of under-fire Dougan's bulking up of investment banking at the time.
The news agency also reports that Rohner also confirmed Saturday that the firm will not sell or spin off its investment bank but is seeking to improve its business model as tighter regulation makes the risky unit less profitable.
'A separation or a sale of investment banking, as is sometimes demanded, would be senseless for our business and our customers', Rohner told the Neue Zuercher Zeitung newspaper.
'It's much more about optimising the business model and better balancing it with regard to capital allocation'.
Finally, AFP reports that Credit Suisse has launched an internal inquiry into the Libor interest-rate rigging scandal but not found any 'significant problem so far', Dougan said on Saturday.
Dougan told Le Temps newspaper that 'although the issue is complex and investigations are on in the bank, we do not think at present that Credit Suisse faces a significant problem in this matter'.
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